http://engineering.twitter.com/ http://engineering.twitter.com/ http://engineering.foursquare.com/ http://engineering.foursquare.com/ http://engineering.tumblr.

http://engineering.twitter.com/ http://engineering.twitter.com/ http://engineering.foursquare.com/ http://engineering.foursquare.com/ http://engineering.tumblr.com/ http://engineering.tumblr.com/ To name a few... know of one, please help add.. Thanks.