Open Gardens:
Advogato —
CIA —
DeviantArt —
FriendFeed —
github —
Google —
Last.fm —
Livejournal —
Ohloh —
Slashdot —
Stack Overflow —
Tumblr —
Twitter —
Wikipedia (en) —
Wikipedia (simple) —
Yelp
Walled Gardens:
Facebook (UCSD & San Diego, Ca) —
IEEE —
Linked In