It is the season when you start thinking about your goals for the next year (or even years). 43 Thinks' Twinkler is a clever little application to inspire you a little bit. Try it out!
I find it interesting for being a rather simple system, yet being much more at the same time through just a little bit of shared awareness among its users! (+ I like the gradual registration)
It is written in ruby (and on rails). And as of now, 87 of its users want to learn ruby, while 64 want to forget ruby :-)
Update: 43 things launched. It's quite interesting to see how it evolves. Try it out!