I think another example, at least for some people, is blogging. Even if you don't have much of an audience, the idea that people are out there who are waiting for you to do something is enough to get some people to do it. I think "show and tell" blogs are the best examples of this - I am willing to bet that people who write about their cooking cook more (and more interesting stuff) than they otherwise would.He's no doubt correct. This reminded me of a friend who blogs about the U Street neighborhood in DC. I can't speak for her, but she's probably seen more of the neighborhood than she otherwise would have, in order to generate blog material. In that same spirit, my fiancee and I hope our wedding blog will inspire us to keep hammering out all the details required to plan a wedding.
Hal's example also made me of think the ABC "Primetime" segment in 2005 that promised to show unflattering bikini photos of participants on the air if they didn't drop lose 15 pounds in 2 months. You can read more about the segment here, which I first learned about from the excellent game theory book "The Art of Strategy." As the book recounts, one participant narrowly missed the cutoff and basically threatened to sue ABC, which subsequently backed off. So ABC's threat wasn't so credible after all.
The examples in this post involve exposing yourself to peer pressure or the threat of public humiliation to inspire yourself to accomplish something. My previous posts, on enrolling in school and buying a Wii Fit, focused on committing money to something in order to guilt yourself into following through with it.
Feel free to send me more ideas if you have them.