For the past several months, I've been working on a new web app/site called Stellar. Stellar helps you discover and keep track of your favorite things online, and currently supports Twitter, Flickr, YouTube and Vimeo. If you like playing around on Twitter or Flickr, you'll probably enjoy Stellar.
I've been using the site for the past few weeks and have really enjoyed it, especially the in-line pics and videos. It's the kind of site I like to browse through at the end of each day.
As I told Jason when he sent me the invite, I don't "favorite" anything, on any service. The most I do is retweet on Twitter. My lack of "participation" had me feeling a bit guilty, because really, I don't contribute anything to the site. Jason said he was totally OK with that, and so I continue to lurk. ;)
Though it may be some time before you receive an invite, you may want to go ahead and reserve your preferred username.