Placepeer is a beta site me and a couple of friends hack on every other Sunday or so. We just felt like it would be nice to go to a place and see what's happening there. Right now we're feeding info from Twitter, Instagram, Youtube and Flickr, but we've built it so it's easy to hook it up with other services in the future. Try it out, or join the development on Github!
Note: since we built this thing a number of services (I'm looking at you, Twitter!) has decided to lock themselves up and severely limit what you can do with their APIs without authenticating. If the team get the time we'll fix the app so that we once again receive results from these services, but at the moment we're not quite sure when or even if we'll be able to get to it.