George Washington - Just to show him what his country became.
Niccolò Paganini - To bring some jism back to classical music.
Nikola Tesla - I can't imagine what new discoveries he would come up with using modern physics.
Haley Paige - I think she still had a lot more to offer, and she never allowed herself to be pigeonholed as "Mexican-American".
Michael Jackson - I would resurrect him, just so I could let his victims torture and kill him again.