Review my Startup - KaBadge.com - Achievements and Badges
vdibart: It's an interesting idea but there are a couple of things you should think through before taking it too much further.  I don't think depending on partnerships is necessarily horrible, but what I'm trying to determine is what the benefit for the partner is.  In the Stack Overflow example, Stack Overflow has to create the logic of when to award the badge, create the badge asset (e.g. what it looks like), and call your service at the appropriate time.  So far they've done all the work for your benefit.  What do they get in return?  This is the kind of thing you might want to think about otherwise it's just a glorified/unified badge gallery, which won't be terribly interesting to many people.I also think your example of other services limiting behavior depending on badges gained on other sites to be unlikely.  From the consumer's perspective, a reputation system has a lot of value in context, but that's very different than saying that my reputation on one site has value on another.  From the partner's perspective, I find it unlikely that I would build a site that depends on my audience's behavior on someone else's site.I don't think these things are deal breakers, you just have to target it a little more precisely.  Nice work so far.