Georges "Rush" St-Pierre (born May 19, 1981), often referred to as GSP, is a Canadian mixed martial arts fighter. He is the current Ultimate Fighting Championship welterweight champion, and is generally regarded as one of the best pound for pound fighters in the world. He is currently ranked by multiple MMA publications as the #1 welterweight in the world.

Anderson "The Spider" Silva (born April 14, 1975), is a Brazilian Muay Thai champion, Brazilian Jiu-Jitsu black belt and mixed martial artist. Since October 14, 2006 he has been the Ultimate Fighting Championship middleweight champion
http://www.spidersilva.com

Charles David 'Chuck' Liddell (born December 17, 1969), also known as "The Iceman" is an American mixed martial artist who fights for the Ultimate Fighting Championship. A former UFC light heavyweight champion, Liddell has an extensive background in kickboxing and collegiate wrestling.
http://www.iceman.tv

Brock Edward Lesnar (born July 12, 1977 in Webster, South Dakota) is an American mixed martial artist as well as a former professional and amateur wrestler. He is the current UFC Heavyweight Champion.

Randy Duane Couture (born June 22, 1963) is an American mixed martial artist, Greco-Roman wrestler, and former collegiate wrestler. Couture is one of the two MMA fighters to have held a championship title in two different divisions (heavyweight and light heavyweight) while in the Ultimate Fighting Championship (UFC) (the other one being BJ Penn), as well as the only five-time champion in UFC history, earning him the nicknames "The Natural" and, later, "Captain America". He is considered by many to be the most popular fighter in MMA history, and is a member of the UFC Hall of Fame.
http://www.thenatural.tv

Jacob Christopher "Tito" Ortiz (born January 23, 1975) is a Mexican American mixed martial artist and former UFC fighter from Huntington Beach, California. As the Ultimate Fighting Championship light heavyweight champion from 14 April 2000 to 26 September 2003, Ortiz emerged as one of the sport's biggest stars, becoming the biggest pay-per-view draw of 2006
http://www.titoortiz.com

Royce Gracie, pronounced Hoyce Gracie (born December 12, 1966) is a professional mixed martial arts (MMA) fighter and Brazilian Jiu-Jitsu practitioner. Gracie became well-known in the mid 1990s with a string of submission victories over larger opponents in the Ultimate Fighting Championship. Between 1993 and 1994, he won 11 matches by submission and was the tournament winner of UFC 1, UFC 2, UFC 4, and fought to a draw with Ken Shamrock in the superfight at UFC 5. These results contributed to the movement towards grappling, cross-training and Mixed Martial Arts.
http://www.roycegracie.tv