Wii Fit
Success: Wii Fit is simple and, for lack of a better term, videogame-y enough for me to become more conscious of my own weight. The anthropomorphic balance board that supervises your Wii Fit activity will offer real-world tips on what makes you real-world fat and a real-world sloth. Semi-regular weighings and balance checks are, I'm convinced, actually making me a somewhat healthier person.
Failure: Playing Wii Fit for more than a few minutes is boring as hell. I originally intended to "exercise" at least enough to unlock all the minigames, but there are just so many better uses of my time that at this point I've completely stopped caring.
I'll continue to weigh myself with it every so often, but I haven't touched an exercise mini-game in weeks and I doubt I will again anytime soon. And since you can do the Body Test using a channel that Wii Fit installs to your main menu, I don't even use the game disc anymore. At least it's convenient.
Progress: Gave Up -- I actually lost weight!