"The Biggest Loser" (NBC)

Hosted by the perky Alison Sweeney, this is one of the few reality competition shows that doesn't humiliate the contestants. The overweight hopefuls embark on a series of increasingly intense workouts and get encouragement along the way.

Highlight: Trainer Jillian Michaels -- what, are you still sitting down?

Incentives: Hey, they're all winners just for showing up and trying. (If NBC's affiliates were smart, each would spin off its own local version with hometown contestants -- there's a free ratings winner idea for you, guys.)

"Celebrity Fit Club" (VH1)

Oh, the schadenfreudeliciousness of it all. To watch celebrities who first admit they're imperfect, and then to revel in their struggles and interpersonal skills (or lack thereof), it all makes for some of the best reality TV. Viewers can have it both ways: Secretly take delight that Little Miss Perfect Marcia, Marcia, Marcia Brady (Maureen McCormick) has packed on a few pounds, and root for her as she works hard to shed them. (Admit it, you totally cheered for her.)

Highlight: So hard to pick just one! We lean toward the very public unhinging of Daniel Baldwin in the first season (did he ever utter a sentence that wasn't bleeped?), with honorable mentions for the Screech screeds from the fifth season, and Gary Busey's Busey-isms ("S.O.B.E.R. and that stands for "Son of a B**** Everything's Real!").

Incentives: Getting back on Hollywood's radar, of course. Though in the case of, say, Baldwin, that can be a mixed blessing.

"Fat Actress" (Showtime)

This ran and concluded in spring 2006, but the aftershocks are still with us. Kirstie Alley's reality show led to her high-profile spokesmodel career for Jenny Craig and a sweet sashay on "Oprah" in a bikini (and, we might cattily point out, a gauzy "wrap" that hid a few sins, but that would be mean).

Highlight: Alley's battle cry: "As God is my witness, I'll never be fat again!"

Incentives: Actual other acting jobs, not to mention the above bikini strut. But this summer the knives are out, and not just at the table. The National Enquirer unkindly reported in July that Kirstie's "ballooned" back up in weight, and that meanwhile new Jenny Craig spokeswoman Valerie Bertinelli has the pounds "melting" away, so that the newest ads feature only Bertinelli and not Alley. Can "Fat Actress 2" be far behind?

"You: On a Diet" (Discovery Health)

Dr. Mehmet Oz and his team of trainers, nutritionists and relaxation experts make this show more of a visual self-help book for those more serious about going straight to designing their own programs. No celebrities, no fat everydudes to follow for weeks, just a great assortment of workouts for every fitness level, plus nutrition tips and more.

Highlight: Dr. Oz: "We love making people smart about their bodies." Who can argue with that?

Incentives: A TV and Web-based community for detailing your own workout and support system. Ready? And one, and two ...