Please name some, past and present.

Dave Brubeck
Billy Taylor
Thelonious Monk
George Duke
Fats Waller
Jelly Roll Morton
Art Tatum
Bill Evans
Herbie Hancock
Oscar Peterson

My two favorites:

Red Garland
McCoy Tyner

Someone will inevitably mention Keith Jarrett (I guess I just did, eh?), so you might want to check out his stuff, too. Personally, I can't stand his work.

Ditto
Thelonious Monk
McCoy Tyner

I'd like to add:
Joe Sample

and my off the wall choice:
Sun Ra

and, of course:
Chick Corea