Manipulation of the time space continum my fav
to speak any language now or historical.......this would also give me the ability to get a taxi in my home town...
read other's mind
I like the idea of being able to turn gravity on and off :)
to heal everyone pain especially heart pain...:)
The power to clone myself. Though that could get out of hand, it'd be very helpful!
I think I would like to see things (by naked eye) at a sub-atomic level.