I believe April 2006 is the original start up date because I can`t find any users who signed up before then. The oldest account that is still active off the top of my head would be ZeroPride.
"If you get hit and it hurts hit him back you not knocked out yet."-Joe Doerksen
The Toxic Terrors (FFL)
Georges St. Pierre*Sarra McMann*Pat Curran*Patricio Freire*Uriah Hall
NP FFL Team Toxic Challenge
Fabricio Werdum*Gilbert Melendez*Rick Hawn*John Dodson*Urijah Faber