Danny of Beeminder here! Thanks so much for enthusiasm about our API! We're really excited about the things people are cooking up. Especially related to Hacker News, here's my Beeminder graph of HN use over the last year: <a href="http://beeminder.com/d/hn" rel="nofollow">http://beeminder.com/d/hn</a> (that's time spent as tracked by <a href="http://tagti.me" rel="nofollow">http://tagti.me</a> but it would be great to have something that measures page loads of news.ycombinator.com directly...)
Ooh! One use we didn't describe in the post is TallyBee -- I added Beeminder integration to a super simple android tally app (it increments a counter every time you touch the screen). Put it on the floor, do pushups. Your nose increments the count at the nadir, and your Beeminder graph is instantly updated. Awesomepants!
One design dilemma we ran into when building this out is the "username" endpoint. When a user grants access, the OAuth default is to just pass the token back to the client. But to access other endpoints, the client needs to know the username of the user that just granted access.<p>So we added the "username" endpoint, but weren't (and still aren't) quite satisfied with that as a solution. Have other API designers run into this same issue? Seems pretty common - would like to hear what HN has to say about it.