On a recent evening, I was scrolling through the channels in the outer reaches of my cable package, looking for something to watch. It was at the end of a long day and I didn't want to see something new, or anything that was challenging or upsetting—I passed right by Noah Baumach's Greenberg and the Coen brothers'Blood Simple. What I wanted to do was shut my brain off and be comforted while my butt melted into the couch cushions. So I was delighted to find The Sweetest Thing, the bawdy buddy flick starring Cameron Diaz, Christina Applegate, and Selma Blair, playing on one of the 14 different kinds of HBO my husband and I have. During the spring of 2003, I watched The Sweetest Thing almost every day, because it was one of three or four movies my university's internal television station played on rotation. Even so, I can't help watching it every time it's on TV.

Mind you, I am not saying The Sweetest Thing is a good movie, not by any critical standards. It has a dismal rating of 32 on Metacritic. Reviewing the movie back in 2002, Roger Ebert wrote: "This is not a good movie." It's certainly not the kind of movie you want to own on DVD—I would never actually seek it out, and frankly I'd be embarrassed to have it on my shelf. I tend to purchase aspirationally, going for the Criterion-approved movies I want to want to see again (Jules et Jim, for example). The Sweetest Thing is also not the kind of movie that needs to be seen in a theater. There are no major special effects. The only thing that's visually interesting about TST is the part when Diaz and Applegate dance around in their underwear to "The Piña Colada Song."

Still, The Sweetest Thing is an ideal movie to watch over and over again on television. TST's easy humor envelops you like a warm blanket. Cable TV programmers seem to know viewers crave this sort of comfort-watching, and so year after year they offer us the same happy endings from Nora Ephron rom-coms, belly-laughs from old Chris Farley vehicles, and the good looks of Hugh Grant. These simple, satisfying flicks are made to be watched on TV

How do you know when you've stumbled on the perfect movie to watch while couch melting? They tend to have two or more of the following qualities:

The plot should be easy to follow: The Sweetest Thing is primarily about female friendship. Diaz, Applegate, and Blair play party-loving BFFs who live in San Francisco. Diaz meets a foxy guy at a club (Thomas Jane), but the two fail to seal the deal that night. She overhears something about a wedding he's planning to attend, so Diaz and Applegate do what any level-headed women would do in this situation: They go on a road trip to the wedding in the hopes of snagging her missed connection. This road trip includes a glory hole, a dress-up montage in which they try on loads of hideous clothes, and simulated girl-on-girl oral sex in a Saab station wagon. I told you, this is not a good movie. And yet, this barely there plot allows the viewer to tune in at any point and still understand what's going on. My Slate colleague Farhad Manjoo says that Pretty Womanhas this same quality: You don't have to worry about misremembering some crucial twist—there aren't any.

You should be able to stop watching it at any point: For those of you who haven't seen any part of The Sweetest Thing in its nearly decadelong victory lap around the TV dial, let me inform you that the glory-hole scene is not even the most lowbrow joke in the movie. That award goes to the scene in which Selma Blair gets her mouth stuck on a certain part of her boyfriend's pierced anatomy. That The Sweetest Thing's humor is utterly mindless explains why it is a good movie to flip to when it's on—it will make you laugh, but there's no chance you will get sucked in. That's the danger with a movie like Goodfellas, another film that is constantly on TV. If I happened upon that scene in which Ray Liotta's up-and-coming gangster Henry first meets Lorraine Bracco's nice Jewish girl Karen, I would have to watch the entire damn thing, even if I had intended to go grocery shopping. (More on Goodfellas below.) One Slate staffer who will not be named (in order to save her the embarrassment) grudgingly admits to spending many a hungover Saturday watching snippets of Joe Dirt with her husband. Unlike a Scorsese film, David Spade's oeuvre does not require neurons, so you won't be compelled to watch all of it or to think about it after it's over. It runs through you like all those Miller Lites you drank hours before finding it. *

The movie should not tax your psyche: Though I am not personally a fan of Mr. Spade's work, except when Chris Farley is involved, appealing stars are a pivotal part of good TV movies. Cameron Diaz is one of these comfort celebrities for me: I can't look at her goofy mug without laughing. Other Slate staffers believe that Paul Rudd is a linchpin of the bland, always-on-cable catnip movie: "I've seen Role Models at least two more times than necessary because of the Rudd Factor," says Slate managing editor Rachael Larimore. Other Rudd movies that you should be watching every time you see them on TBS and/or Comedy Central: I Love You, Man; Clueless; and Forgetting Sarah Marshall.

Sometimes it's not a star's particular charisma, but a director's reliable touch that makes a movie soothing to watch on TV again and again. Co-workers mentioned Nancy Meyers, whose aesthetic was once likened to cashmere in the New York Times Magazine, as such a director. Who wouldn't want to spend a few minutes transported to the tasteful-yet-cozy upscale white interiors of the pad in Meyers' Something's Gotta Give while doing some mundane task like folding laundry?

Back to Goodfellas for a second. There are a few films that get a lot of television airplay— Shawshank Redemptionis another example—that explore disturbing subjects, demand to be watched in full, and often have complicated plot structures. Though they're nothing like a piece of fluff like The Sweetest Thing, they inspire a similar comforting feeling in the viewer. In such films, the characters are so strong, the story so gripping, and the pace of the movie so engaging that they're a treat to find when you're flipping through the channels—even if they defy all the rules set out above.

While I'm powerless to resist the charms of Cameron Diaz and company in The Sweetest Thing, I acknowledge that song-and-dance routines about penises aren't for everyone. So I asked for suggestions from my colleagues of movies they must tune into whenever they see them on television. Please take the poll below to let us know your favorites. This poll is by no means complete, so if we missed one, leave your enthralling-when-on-TBS picks in the comments below. I'll post a follow-up with the results.

Correction, Feb. 16, 2011: This article originally misspelled Miller Lite. (Return to the corrected sentence.)

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