London is known for his long curly hair and bib overalls. His signature line is "You might recognize me, I'm the fourth guy from the left on the evolutionary chart," referring to his slouching posture and unkempt appearance. His comedy is usually self-deprecating and laden with quips such as "0 for 1", "This is death!" and his trademark line, "It's almost over." During his run on Last Comic Standing, he made a guest appearance on The Tonight Show with Jay Leno. After Last Comic Standing, London joined fellow Season 2 competitors Gary Gulman and Alonzo Bodden as part of the "I'm Still Standing" comedy tour. He has also done shows for cancer patients and small comedy clubs. In 2004, Jay made an appearance on the game show Street Smarts; in 2005, he appeared on the CBS sitcom The King of Queens, on the TBS reality show Minding the Store and Bravo's All-Star Reality Reunion.