The top ten movies starring 'Grey's Anatomy' actors

In honor of the start of  the summer movie season, which will feature Katherine Heigl hitting the screen in The Ugly Truth, and Jeffrey Dean Morgan making an appearance in Taking Woodstock, let's take a look at the best movies starring 'Grey's Anatomy' cast members:

10. 27 Dresses (Katherine Heigl): This light romantic comedy is perfect for a rental on a lazy summer night, especially for anyone faced with the thankless task of serving as a bridesmaid this summer. Heigl plays a charming but perpetually single woman who gets her kicks by planning her friends' weddings. Sound familiar?

9. Twilight (Elizabeth Reaser): Could it be possible that when Ava/Rebecca left Alex to seek psychiatric help at the end of season four, it was all just a ruse to cover up the fact that she's a vampire? In the hit supernatural teen romance. Reaser continues her residence in the rainy state of Washington as the maternal figure to a family of angst-ridden teen vamps. She'll reprise the role in the upcoming sequel, The Twilight Saga: New Moon.

8. Watchmen (Jeffrey Dean Morgan): The erstwhile Denny Duquette lives on, and shows off a completely different side of his personality as the amoral crime-fighter The Comedian in this recent adaptation of the legendary graphic novel.

7. Under the Tuscan Sun (Sandra Oh): Before beginning her residency at Seattle Grace, Oh spent some time taking in the gorgeous scenery at the Italian villa of her friend Diane Lane. (Warning: watching this movie has been known to cause the urge to drop everything in  your life and run away to Italy.)

6. Old School (Ellen Pompeo): Dark and twisty Meredith got to laugh it up for a change in this raucous comedy about a group of 30 something dudes who try to recapture their glory days by starting a fraternity.

5. Enchanted (Patrick Dempsey): 'Grey's' probably isn't a good choice for family viewing, but this Disney musical is the perfect opportunity to introduce children to Dempsey's McDreamy magic.

4. Knocked Up (Katherine Heigl): Heigl gives a performance that's both hilarious and deeply real in this instant-classic comedy about the consequences of ill-advised one-night stands.

3. Can't Buy Me Love (Patrick Dempsey): To many people who remember the 80s, Dempsey will always be most remembered for this classic teen comedy, in which he played a nerd who hired the prettiest girl in school to pretend to date him.

2. Trainspotting (Kevin McKidd): Years before Dr. Owen Hunt showed up at Seattle Grace to yank out Cristina's icicle, McKidd made his mark alongside Ewan McGregor and Johnny Lee Miller in this harrowing, inventive look at heroin addiction from Slumdog Millionaire director Danny Boyle.

1. Sideways (Sandra Oh): Anyone who enjoys fine wine or the beauty of California's Napa Valley will enjoy this intelligent buddy comedy about a pair of middle-aged men on a life-changing road trip. And any fans of Cristina Yang's tough side will love the scene in which Sandra Oh beats Thomas Haden Church to a bloody pulp with a motorcycle helmet.

Check back soon when we'll take a look at the other side of the spectrum and rate the worst movies starring 'Grey's' cast members. And for more ideas on how to keep yourself entertained over the summer, check out these tips for surviving the 'Grey's' summer hiatus. For more on what the cast is up to when they're not shooting, make sure to take a look at last week's photo round-up.

As always, feel free to weigh in with your thoughts in the comments section. What's your favorite movie starring a 'Grey's' actor?