SocialWhois » Home Page
http://www.socialwhois.com/

While the names of some new followers I get on Twitter or Friendfeed immediately ring a bell, with others, I have no idea who the person might be. Typically, I can make a “re-follow decision” within a few seconds by checking out their profile and clicking thru to whatever links they provide, but for those looking for another layer of detail, Socialwhois is a new service you might find somewhat useful. Much like a domain name whois, Socialwhois provides additional data for a username on Friendfeed or Twitter. By default, this appears to be done by trying to cross-reference the two sites – for example, before signing up, Socialwhois seemed to associate my Twitter username with several other accounts that are listed on my FriendFeed profile.