I've created two March Madness brackets, mainly for another site I post at but I figure I'll make a post here for anyone who wants to join in on the fun. One is on Yahoo, another on CBS Sports.
Yahoo
http://y.ahoo.it/etjvcrrHGroup ID: 281701
Group Name: Blog of Doom
Password: cruise
CBS Sports
http://rspwfa2.mayhem.cbssports.com/Password: cruise
Let me know if anyone has trouble accessing or signing up.