There's no escaping the concept of friends with benefits (FWB) these days. It has even inspired two big releases this year: 'No Strings Attached,' starring a 'Black Swan' diva and a former teen heartthrob, and 'Friends With Benefits,' starring, well, a 'Black Swan' diva and a former teen heartthrob.

The latter hits theaters this week, with Justin Timberlake and Mila Kunis playing the FWBs in question. The two gravitate towards each other after they're dumped by their respective mates (Emma Stone and Andy Samberg). Neither wants a big commitment after being burned, so they make a pact to treat sex like it's no bigger deal than a friendly game of tennis.
The two flicks certainly have more similarities than differences, but 'Friends' does a better job of establishing the friendship aspect of the FWB arrangement. Kunis and Timberlake's characters joke around, play video games and actually seem to enjoy each other's company out of the sack.

'Friends With Benefits' has two key things 'No Strings Attached' doesn't: Woody Harrelson and Patricia Clarkson. Harrelson is hilarious as Timberlake's gay jock co-worker who's not afraid to dish out very blunt advice, and Clarkson also shines as Kunis' kooky mom.

Of course, 'Friends With Benefits' and 'No Strings Attached' aren't the first to explore what happens when you mix sex and friendship. While we have FWBs on the brain, here's a list of my own top five favorite movie friends who blur the line between friends and lovers.

1. Harry and Sally (Billy Crystal and Meg Ryan) in 'When Harry Met Sally.' Forget the benefits. This movie raised the question 'Can men and women ever be just friends?' While Harry and Sally don't have a FWB arrangement, they do rely on each other for a lot of couple-y things, like dinner companionship and late-night phone calls. When they do hook up it's really more of an 'oops' than a concerted decision to throw sex into the friendship, but I would still argue that Harry and Sally are the ultimate movie friends with benefits.

2. Ennis and Jack (Heath Ledger and Jake Gyllenhaal) in 'Brokeback Mountain.' Their wives reckoned they were just friends. But Ennis and Jack certainly enjoyed a lot of benefits on those fishing trips. The two men shared a lot of similar interests, which made them the ultimate friends with benefits. Fishing, cowboy stuff and sex? What a great deal! Too bad love had to get in the way of this otherwise pretty sweet arrangement. Someone always wants more!

3. Lelaina and Troy (Winona Ryder and Ethan Hawke) in 'Reality Bites.' Much like Harry and Sally, Lelaina and Troy's initial hook-up was more of an 'oops' than a plan. Instead of parlaying it into a formal FWB situation, the two try to pretend it didn't happen and ignore their attraction to each other. A FWB arrangement would have been convenient since they lived together. Though, I suppose, living together would probably make it more difficult to avoid getting emotionally attached. They give in to their attraction in the end, bypassing the FWB stage in favor of a full-blown relationship. Typical!

4. Matthew, Isabelle and Theo (Michael Pitt, Eva Green and Louis Garrel) in 'The Dreamers.' Matthew totally scored. He not only got to hook up with the super-hot Isabelle, he also got a great place to stay in Paris. Too bad her brother Theo is always trying to horn in on the action. Oh well, they're all friends. With benefits. Am I the only one thinking of the 'Three Best Friends' song Zach Galifianakis sang in 'The Hangover' right now?

5. Steve and Linda (Campbell Scott and Kyra Sedgwick) in 'Singles.' In the '90s, before we had terms like FWB, people just tried to 'keep things casual.' (Ah, '90s cool. Nostalgia alert!) Steve and Linda hit it off, but they don't want to get too serious. When they try to be just friends, their mutual attraction escalates things pretty quickly. They're hot, they're cold, they're hot. Clearly, this casual thing just doesn't work out sometimes.

-- 'Friends with Benefits' photo by David Giesbrecht
Friends With Benefits
Based on 37 critics

Complications unfold when two friends (Justin Timberlake, Mila Kunis) add sex to their relationship. Read More