There are certain things that are no-brainers when you're flying. Obviously you can't bring sharp objects or firearms onto a plane with you. Of course, that doesn't mean people don't try. There are thousands of guns, knives and other weapons confiscated every year in airports across the country and around the world. These people often hold-up flights for hours, arguing with airport security that they aren't going to use their weapons, but they'd like to have them in case someone else tries something.

Simple guns and knives aren't that strange, as we expect a few people to try their hand at transporting weapons every now and then. The real interesting stuff is what falls in a grey area of sorts; things that might be allowed on a plane but probably shouldn't be. Some of these bizarre items were actually allowed to fly, which makes no sense whatsoever. Other people try to pull one over on airport security, transporting things that they know (or at least should know) are not allowed by attempting to sneak them on. This list encompasses some of the most bizarre items that were actually allowed to fly alongside those that obviously weren't. You can't blame some of these people for their efforts, as sometimes you just have to have some live fish in your briefcase to feel comfortable thousands of feet above the ground.

15. Venomous Snakes

According to the TSA blog, one man in Newark tried to smuggle some venomous snakes onto a plane (insert your Snakes on a Plane reference here). Fortunately, the snakes were already dead, but the most surprising fact out of this story is that you are actually allowed to ship dead, venomous snakes. The only thing that held up this passenger was the liquid that the snakes were being transported in. Apparently they set off the explosive detection alarm and had to be inspected further before they were allowed to fly. It's a happy ending for this passenger, as he was able to bring his snakes back home for a proper funeral. The moral of the story is: make sure your dead snakes are packaged in the right kind of liquid. I know, I know, you've heard it a million times from your parents, but I want to make sure we're all on the same page.

14. A Cannonball

A cannonball seems like a pretty good souvenir idea, especially for a history buff. One Ft. Lauderdale flyer tried to take one home on a plane with him in 2012, though, he learned the hard way that it's not allowed. This wasn't some gift shop cannonball either, as the man was a diver and found the cannonball near a shipwreck under water. First of all, imagine how much weight he was adding to his luggage by bringing it - that's dedication right there. Apparently cannonballs can hold their explosive properties for years and just explode with no warning, sort of like hoverboards. I'm sure the 290 passengers who were delayed were not amused when they found out that some knucklehead tried to bring a cannonball on board.

13. Carry-On A Dog

Dogs are obviously allowed to fly, but they aren't allowed to sit on the plane with you. Airport security in Dublin had to tell one man this in 2009 when they spotted a pup in his carry-on luggage. They initially thought the dog was a toy when they spotted it in the X-ray machine, and were surprised when they opened the man's bag and found a live Chihuahua inside. Dog bags are all over the place on TV, so I'm sure this man thought he would be one of many people to bring his dog onto a plane with him. This is not the case, and as cute as it might be to see a little dog running around the plane, I'm sure the annoyances outweigh any joy that other passengers may get.

12. Fire

One person in Atlantic City tried to smuggle home some flames, claiming they were just the clothes he was wearing while he was "on fire" at the casino. That's obviously just an alternative fact (Google Kellyanne Conway if you need context for this reference). The real story is that one unsuspecting flyer packed their belongings a little to carelessly, placing flammable liquid next to a notoriously flame-producing device: a lighter. The flammable liquid, in this case hair spray, leaked into the passenger’s bag and caught fire, causing three-foot-high flames to erupt from the culprit's suitcase. Fortunately the bag erupted on the conveyor belt and not on the plane, but this was undoubtedly quite the hold-up for anyone who was checking luggage that day.

11. Gassed-Up Chainsaw

I know what you're thinking: "A chainsaw?!? What are these people thinking? You can't even bring a bottle of water on the plane!" That's an apt observation anonymous Richest reader, but it wasn't actually the chainsaw that was a problem. Authorities seized the chainsaw that was in a flyer's checked luggage, but only because the chainsaw had gas in the tank. You can actually fly with your chainsaw, so there's no need to cancel you flight to the next logger convention. The problem here was the gas, as it's (obviously) highly flammable and dangerous to have on board an aircraft. The bizarre realization here is that you can actually fly with your favorite chainsaw, provided you run out the gas before you hop on the plane.

10. Live Fish

It isn't the fish that are the problem, as airlines will ship fish for you if packaged correctly. Sometimes you just can't leave your fish tank at home when you go on vacation, and in these instances you are allowed to bring fish onto the plane with you. One man, however, decided to take his 240 fish with him using nothing but briefcases. That's right; this passenger thought it would be a good idea to bring 240 of his favorite fish in a series of briefcases filled with water. I'd love to know why this person wanted to bring all of these live fish with him in the first place, but I can kind of understand if he thought it wouldn't be problematic. You can bring a lot of random things onto a plane, and you can't blame him for trying; shooters shoot.

9. Boomerangs

If you're looking to bring home an authentic Australian boomerang, the Australian authorities have no problem with you bringing it on a plane. They apparently haven't experienced the wrath of a boomerang like the Americans have, as you'll have to check that boomerang once you get on a plane to the US. You won't be able to play catch with yourself on a US-bound aircraft, as the United States considers boomerangs to be a deadly weapon. I know boomerangs are a hot item out there, so keep this in mind so you're not holding up the flight next time you want to bring home this lonely toy. Though there have been no instances of someone trying to hijack a plane with one of these, I guess you can never be too careful.

8. A Body

This may sound wild, crazy or downright spooky, but it's actually quite understandable if you consider the extra cost involved with shipping a corpse across the country. These people aren't murderers trying to ship a body out of state; they're just regular people trying to save a buck. I've never done it myself (knock on wood), but the fee for sending Nana back to Boston for her funeral can cost you around $6,000 when it's all said and done. People have been killed for less, and not everyone has the kind of cash to be shipping dead bodies back home at a whim. This is why multiple people have tried to game the system by slapping some sunglasses on Gramps and hoping for the best. It usually doesn't work, as there are about five obstacles I can think of off the top of my head that would make this impossible, but you have to respect the effort. Hell, some people may have even been successful. We only hear about the failures in these stories, never about the guy who saved six grand by flying his dead grandfather coach.

PS: Credit to me for getting through this description with zero Weekend at Bernie's references. That's just good writing.

7. Severed Heads

I hate to disappoint you, but this wasn't a serial killer trying to bring home a souvenir for his talking dog. The person shipping these 18 severed heads was actually a medical professional with proper paperwork. The reason was never given for his packages, but according to TSA it's not unheard of for body parts to be shipped commercially. The confusion came with the paperwork, when the heads were sent to the wrong airport. Anyone opening these must have experienced quite a shock, but the Department of Homeland Security had seen this kind of thing before and was not shaken. They checked the paperwork and sent the heads to their destination. The fact that this seemed to be a routine problem makes you wonder: what kind of wild stuff is would surprise these people (by the way, this photo is likely a replica, not the real deal)?

6. Skull Fragments

When you go to a new place, you get a souvenir; that's just vacationing 101. I don't think this is just an American thing either. People from around the world are gathering key chains and coffee mugs from their travel destinations, if for no other reason than to prove to their boss that they actually went. Unfortunately for one couple, the souvenir from their trip to Ft. Lauderdale caused them quite the headache (pun intended) when they were trying to get back home. The clay pots the two were planning on bringing home ended up containing fragments of a human skull.

There was no real explanation as to how the skull got into the pots in the first place, but the couple claimed to have no knowledge of why there would be any human bone in their novelty pots. It's hard to say if I believe them, as they could have been low-key trying to get a souvenir from their Ft. Lauderdale murder vacation. The couple was allowed to leave, but had to forfeit their souvenirs to the authorities, who kept them as evidence in a murder investigation. I hate to do it but I gotta call a spade a spade here: when you buy anything in Florida you have to assume there's a 90% chance your getting something that was someway involved in a murder.

5. A Baby

This gives a new meaning to "baby on board", am I right?? This couple likely won't win any award for parenting, as they were stopped when they attempted to smuggle their baby onto a plane in the United Arab Emirates. The baby didn't have a Visa, and they wanted to get it home the easiest way possible. Of course, they were stopped when they put their young child through the X-ray scanner. The attendants could see a living thing in one of the parent’s carry-ons, and alerted authorities immediately. It’s unclear if there was any action taken against the parents, as apart from this being incredibly stupid, it probably endangered the long-term health of their child.

4. Cockroaches

In some cases, people bring unwanted guests onto an airplane without knowing it. In this case, it was in the food. LSG Sky Chefs and Gate Gourmet were only two of the catering companies that were marked as having unsanitary conditions in their food. They were found to have mice, cockroaches, flies and other pests running around in their food, which made its way onto the plane. The vermin didn't cause any harm on board, as they appeared to have no malicious intent, but it's still pretty disgusting to think that your airplane food could have been trampled on by some little critter like a cockroach. Cockroaches are the hallmark of unsanitary conditions, so it might be worth your time to pack some snacks for yourself next time you take a trip.

3. A Tiger Cub

In 2010, a woman was attempting to fly from Bangkok to Iran but was stopped when she was discovered to have a sedated tiger cub in her luggage. The bag she was carrying was full of stuffed tiger toys, making the tiger cub less noticeable to authorities (or at least she thought). She claimed that the bag wasn't hers, but based on my extensive Cops research that's what pretty much everyone says in this situation. Apart from this being a pretty mean thing to do to a two-month old baby tiger, I'm sure finding this tiger saved the life of at least one or two people. Based on how she tried to smuggle it in, I doubt this woman had any experience dealing with tigers. Still, I wonder if she was trying to sell this tiger cub or if it was a, "OMG it's so cute I have to keep it," type of situation.

2. Basically a Zoo

While there have been multiple animals unsuccessfully smuggled onto airplanes over the years, this South African man topped them all in 2009. He was returning from Thailand, a place with seemingly relaxed airport security, and was arrested after authorities found what he was traveling with. The man had 70 live animals with him, including multiple snakes, scorpions, Caiman crocodiles and turtles among others. The animals were confiscated and quarantined, as is routine when some turkey brings a bunch of foreign animals with him to a new country. As stated above, the man was arrested and probably convicted of trafficking animals from out of the country. There's a few stories of people traveling back from Thailand with some exotic animals, so they might want to tighten things up over there.

1. Live Pigeons

Yup, you read this right; live pigeons. An Australian man went viral in 2009 for being caught with two live pigeons stuffed in his pants. The man was returning to Australia from a trip to the Middle East when he was stopped at customs. Authorities found two eggs in a vitamin container, along with some seed in the man's luggage and decided to search him. They then found that the man had two pigeons, each placed in an envelope and strapped to his legs under a pair of tights. Smuggling wildlife is a serious crime, and in Australia the maximum penalty is 110,000 Australian dollars ($70,430) and up to ten years in prison. I don't know if the crime is worth the punishment here, but I have so many others that I kind of need answers to. First of all: Why? 2) Why the eggs? And, 3) How can you trust two birds to sit quietly and contently in your pants for an entire flight? Forget the purpose of conscious life in the universe. I need to find out this man's life story yesterday.

Sources: NBCnews.com