As we know, lots of celebs date other celebs, and hey, why not? We would happily do it, too, if we had the chance to get down with a babe like the stunning Jennifer Lawrence or canoodle with the ripped and tanned Zac Efron. Some stars even meet on the job while filming movies, taping TV pilots, or during auditions. And some of these celeb couples are lucky enough to not only work together but also film love and sex scenes with one another. Talk about bringing work home with you or vice versa.

But then there comes that awkward situation when cameras still must roll even when the couple has called it quits. The saying “The show must go on” applies to exes, too. So these broken-up duos must continue to kiss and make out in front of fellow actors and a full production team when personally, the sizzle has fizzled. Isn’t that why they get paid the big bucks after all?

Then, for the more fortunate pairings, they get to film while they're still hot and heavy in real life – method acting, some may say. Knowing they're really in love (or lust) and not just making believe for the cameras is exciting for some, but a little too up-close-and-personal for others. It’s like we're “Peeping Toms” watching their homemade sex tape.

Here are a bunch of exes who still had to get it on for the job and another handful who were more than happy to get paid to “get laid” by their significant other.

Exes: Cameron Diaz and Justin Timberlake

You may have forgotten that the impossibly good-looking Cameron Diaz and the equally impressive Justin Timberlake once dated. But like many A-list Hollywood couples, the two eventually broke up. But that doesn't mean they won’t take roles for movies if the pay is good. The two starred in the hilarious film Bad Teacher together in 2011, despite the fact that they were once a steamy couple and no longer dating during the time of filming. In the movie, there were lots of sexual scenes featuring the duo, and they're either superb actors by not allowing their past to disrupt their work, or there was still something between them. No matter, the chemistry was there, and the movie was a success. Some may even say this is a great way to get in one more shot with an ex!

Exes: Megan Fox and Shia LaBeouf

The sexy and gorgeous actress Megan Fox is a married woman and mother these days, but back when she was single, she dated the actor Shia LaBeouf, and they were stars in the action movie Transformers together. Although their dating time and time filming didn’t overlap, the two actors were sheer professionals and made their chemistry on screen look like the real deal. Hmmm, maybe they still felt a spark. Then again, there aren’t too many fellas in the world that don’t feel at least a little something for the foxy Fox. While the two didn't wind up together as a long-term couple, the movie was a major hit with audiences, and the actors also starred in the sequel together. Too bad for LaBeouf that the make-believe romance couldn't transform into a real-life relationship!

Exes: Kaley Cuoco and Johnny Galecki

Big Bang Theory fans can’t seem to get enough of the show’s grossly overpaid stars, and the relationships between the characters keep audiences tuning in week after week to find out what will happen next. Two of the show’s hottest stars, Kaley Cuoco and Johnny Galecki, are not only coupled up on the program but were a real-life couple for a while as well. But of course, like most celeb pairs, the two went in opposite directions… until they got to work and had to pretend to be in love for the cameras. It’s a good thing these two got paid the big bucks or else they may not have been able to stomach smooching one another in character. But good actors must put their own issues aside and follow the script. Heck, kissing Cuoco can’t be that awful for the actor. Lots of guys would gladly step in for a fraction of his salary.

Exes: Rachel Bilson and Adam Brody

Fans of The O.C. adored watching the adorable on-screen couple of Summer and Seth, but the two in real life – Rachel Bilson and Adam Brody, were a couple as well. Aww, wasn’t that sweet? But the real romance didn’t last as long as the TV show one did, so the cute couple had to keep on doing their thing on screen even though things went cold in their off-screen lives. Sure, young love is fickle, so it isn’t a shock that this brunette couple didn’t make it to the altar, but going to work each day and smooching for a salary had to be awkward and slightly, if not totally, uncomfortable. At least the viewers got to watch this good-looking duo lock lips; too bad for them, there were no real sparks left between them.

Exes: Kirsten Dunst and Tobey Maguire

Oh, what a tangled web they wove when actress Kirsten Dunst and actor Tobey Maguire not only dated in real life but were lovers on film in their action movie, Spider-Man, as well. But their real-life romance ran its short-lived course, and the exes still had to film their Spider-Man sequel as a broken-up pair. While the ex-lovebirds acted phenomenally and their obvious chemistry was lit on the big screen, their time on set must have been super-awkward since their actual lives turned out far different from what we saw onscreen. Even superheroes have flaws, apparently, and Maguire couldn’t keep Dunst tangled in his web of seduction out of costume. At least, the movie brought in big bucks even if their love affair fell flat. Peter Parker was far more interesting to the actress anyhow.

Exes: Jennifer Lawrence and Nicholas Hoult

While making out with the sexy J. Law isn’t exactly a jail sentence, actor Nicholas Hoult had to film some sultry scenes with his ex for the film X-Men: Days of Future Past, making the breakup all the more uncomfortable. The good-looking duo met while filming X-Men: First Class but broke up and then had to continue filming together, part of which was a hot and heavy love scene. Don’t recall that scene in X-Men: Days of Future Past? That’s because it was left on the cutting room floor. So all that awkwardness between the exes was a waste. But maybe not… That said, the couple got back together after filming, so perhaps Hoult did something right! Then again, they broke up again, and now the couple is history. Talk about an Ex-Man!

Exes: Blake Lively and Penn Badgley

XOXO Gossip Girl here. If you’ve ever watched the steamy teen and 20-something TV drama, then you know there were lots of romances blooming between the characters. And some of this sexiness made its way off set, and actors and actresses got together in real life, too. That was the case for the seductive Blake Lively and hunky Penn Badgley, who were two of the biggest stars on the hit series Gossip Girl. They actually dated for 3 years, but, like many celeb pairs, broke up. That said, their on-screen couplehood was still going strong, meaning they had to hook up for the camera while broken up in real life. Unless their break up was a mess, it’s not like kissing one another had to be disgusting or anything. But perhaps, they were on bad terms, meaning their acting skills had to be far greater than their distaste for one another. At least, the viewers got the thrill of watching these sexy stars on screen in a fairy tale romance.

Exes: Katie Holmes and Joshua Jackson

Before she was Mrs. Ex-Tom Cruise, you will recall the lovely and talented Katie Holmes starred alongside actor Joshua Jackson on the popular “teenage love” hit television program, Dawson’s Creek. The two actors fell in love in real life as they played romantic interests on the show as well. But like most young love, the real-life couple called “cut” while the cameras were still rolling to film their characters’ romance continue on to fulfill the show’s plot. Playing the roles of Joey and Pacey may have been a blast when the two actors were together for real, but getting it on for the production team when their hearts weren’t in it anymore had to make them feel like they were up $#it’s Creek! It wouldn’t be a shock if Holmes wishes she’d stayed with Jackson after her seemingly unusual love affair with her ex, Cruise.

Couple: Jenna Dewan-Tatum and Channing Tatum

They say you can tell how a person will be in bed by the way they shake it on the dance floor, so perhaps that is what attracted Jenna Dewan to Channing Tatum (or vice versa) when they met and fell for one another while filming the movie Step Up. The incredibly sexy pair steamed up the set and couldn’t resist becoming a couple in real life as their characters did in the movie. Both have great dancing and acting skills and are adored by audiences so it wasn’t a shock to anyone that the two became involved with one another and eventually married and had a baby. Dancing and romancing went hand-in-hand for this sexy couple and if they keep up the moves, their relationship will always be a step up from the rest!

Couple: Jennifer Lopez and Ben Affleck

Remember when J. Lo and Ben Affleck dated? Heck, they even became engaged at one point. But while they were a couple, still going hot and heavy, they filmed the widely-panned film Gigli together where they had plenty of love scenes. While the couple didn’t announce their real-life romance during filming, it came out after the film wrapped that the two were wrapped up in one another. Of course, each star eventually went their own way, got married to others, split from them, and so on and so forth. But Lopez and Affleck are two of the hottest A-listers of the day, so surely they have plenty to be happy about, even if Gigli was a bust and their relationship was one as well. At least while filming, the two were happy and in love/lust and the love scenes were more realistic than audiences could have guessed!

Couple: Goldie Hawn and Kurt Russell

One of the longest lasting romances Hollywood has ever seen is that of long-time actress Goldie Hawn and seasoned actor Kurt Russell. While the couple never officially tied the knot to become “man and wife,” they have been faithful and dedicated to one another for decades and prove that a piece of paper doesn’t make a couple any tighter. They were involved in a romantic relationship when they filmed the hilarious and classic movie Overboard and they had plenty of make-out scenes together. Playing alongside one another on set must have been a real hoot for the good-looking pair who were relatively fresh in their romantic relationship at the time. If they were to act in a movie together now, it would be like second nature. Nothing to go overboard about!

Couple: Reese Witherspoon and Ryan Phillippe

Who knows what their intentions were, but the now A-list actress Reese Witherspoon and the handsome and talented actor Ryan Phillippe fell in love while filming the teenage classic hit movie, Cruel Intentions. This couple was the “it” pair for some time among the young Hollywood crew, and they even went the full distance and got married and had two children together. But just like many other famous pairings, the cute couple split up and got divorced. Both eventually remarried and had other kids with other partners as well. But while filming this fun-to-watch film, the up-and-coming stars had stars in their eyes for one another, and the chemistry was evident in every scene they filmed together. Love can be cruel and the two didn’t last forever, but at least it was steamy while making their movie!

Couple: Jada Pinkett Smith and Will Smith

The long-time Hollywood A-list couple, actress Jada Pinkett Smith and actor Will Smith are still together, despite rumors that their romance is sometimes on the brink of crumbling. That said, they are indeed married and were a couple while they filmed the movie Ali together. Who knows if the rumors about them are true, but the two always seem to be in love and have super-strong chemistry, both on film and in real life. Ali was a hit and so were the two actors who showed that a real-life couple can act together and go home and keep the flames of romance burning strong. They are both extremely talented, great-looking, and seem like a fun-loving couple, so it is no surprise that they are terrific on-screen as a make-believe couple and even better as themselves!

Couple: Courteney Cox and David Arquette

Fans screamed when they learned that the unlikely couple, Courteney Cox and David Arquette, were not only a match on screen in the hit horror movie Scream, but were also paired up in real life too. The two seemed like an unusual pairing – she being more like “America’s Sweetheart” and he coming across as sort of an oddball, but opposites did attract and the fun-loving duo became not only a couple, but a married one at that. They even had a child together. While they did divorce, the pair seemingly remain pals and co-parent their daughter and have moved on to new romances. But at least the pair were a romantic couple while filming, which must have been a blessing for the two who got to spend day-in and day-out with the one they loved (at the time).

Couple: Sienna Miller and Jude Law

While filming the movie Alfie, the talented and beautiful actress Sienna Miller fell for her co-star, Jude Law. The characters had chemistry and this trickled down to the stars’ real lives as well. The couple even got engaged to one another and planned to be together until the end of time. But this time was cut short when Law misbehaved and got it on with his kids’ nanny. It’s always the nanny, isn’t it?! The couple parted ways and got back together to give it another go, but then called it quits for good. This couple seemed like they could have been the perfect pair, but once a fella cheats, especially with the kids’ nanny, it’s not a good sign that the romance will be repaired. That said, they were a pair while the movie was filming, so at least the chemistry was intense at the time.

Sources: teen.com; moviepilot.com; popsugar.com