Historical? Damned if I know. Can't think of a single person. Seriously. If we're talking 20th-21st Century famous people that's easier.
I've always wanted to game with the late, great Robin Williams, who I happen to know was a gamer. Those who've followed this site know I have so brief, but awesome history with the departed actor, and comedian and it would have been awesome to have had him at my table.
What game? Would it matter? We're talking Robin Freakin' Williams! At the same time...something Sci-Fi. Probably Star Wars, Star Trek, or Traveller.
My other thought is Jim Henson. Man oh man. Wouldn't it be just the be all, end all to have Jim Henson run a game of Ars Magica? That would be so sweet.
My current groups? Not sure. Maybe...I got nothing.
My older groups?
The Great Gonzo for Toon, Teenagers from Outer Space, Paranoia, Tales from the Floating Vagabond, Hunter Planet, or Gamma World (which he would enjoy for the 'realism' O_o ).
Robin from Young Justice Season One in any of our Superhero games.
Finn from Star Wars: The Force Awakens for Star Wars, Star Trek, and Traveller. Different games, with different approaches to Space Adventure. I think I am imagining gaming with John Boyega more than the character, but I'd love to see how he addresses each setting.
That's all I've got.