UPick games are common in Chat Mafia. The players send in a potential role name, such as Fox Mulder, to the Game Moderator. The moderator will then create a role based around the role name. Sometimes players may fish for a particular role type (for example, fishing for Mafia by sending in 'Don Corleone'), but trying to 'outwit' the mod in such a manner generally does not work. A number of UPick Mafia games have been run in the forums now, often as Theme Games.
Invented by AniX.
AniX's Totally Official* History of UPick
Orginally designed by AniX as a tool to stretch one's abilities at creating roles "on the fly", it has evolved into more of a "what will the mod make this character" type of thing. Orignally, it was called "You Pick" and restricted roles to Pop Culture Fiction. Eventually, it was shortened to UPick for convenience and the restriction was dropped (except in certain cases, such as Theme Games or sometimes AniX will enact traditional rules when he mods).