I've been working on a side project called Streak.ly with a friend of mine for the past month or so; it's intended to help keep you motivated to do otherwise mundane daily tasks (like do 10 pushups, read for an hour, etc.) by letting you log "streaks" — consecutive days in a row of doing something.
It's in private alpha/beta/gamma/whatever right now (has some rough edges to clean up), but is more or less functionally complete and pretty stable.
I'm a big fan of the Seinfeld calendar, and have seen other services which do similar things but were unsatisfying to use, either from an aesthetic or functional perspective. Streak.ly is designed to be simple, good-looking, fast, fun, (and hopefully addictive). (FWIW, it's also a place to experiment with user stickiness stuff I can potentially roll back in to Forrst.)
There are also some in-progress social/game/motivational features I plan to roll out in the next few weeks that hopefully contribute to the enjoyment factor of the app.
Streak.ly uses Twitter for authentication, and I've set up a URL to let HN folks in early: http://streak.ly/auth/twitter/start?secret=showhn
I'd love any and all feedback and/or criticism you may have.
Thanks!
Generate a unique URL for me to use, or hash my email address or something like that. Reduce friction, I want to be able to use this with 1 click.