My favorites in no particular order: Nicky Hopkins, Billy Powell, Billy Payne, Chuck Leavell, Dr. John, Jerry Lee (The Killer) Lewis, Billy Preston, Professor Longhair, Pinetop, Jelly Roll Morton, Ian Stewart (Stewie).

For pure technical wizardry on the keys, Keith Emerson of ELP is amazing.

Also be sure to check out the Russian girl on youtube videos – VKgoeswild. It’s cool to see rock songs interpreted in a Russian classical style. This girl sure can play.