http://www.eol.org/

This site is the brainchild of E.O. Wilson, trailer here:

http://www.videosift.com/video/The-Encyclopedia-of-Life

 TEDtalks here:

http://www.videosift.com/video/2007-TED-Prize-winner-EO-Wilson-on-TEDTalks

I think its under some heavy traffic today, because it seems to be unavailable half the time. Its "only" got a million species so far, but check it out!