Some of my favorite players are:
Chick Corea
This is by far my all time favorite player. He is using tons of different keyboards and effects, but you can always now when it is Chick who is playing. That signature tonality, sound and feeling is so original. I love his work in Return To Forever which are one of my favorite bands. By far the most original, innovative and soulfull player i know!
Jan Hammer
His work in Mahavishnu Orchestra is outstanding. He has incredible funky feeling and rough sound, which i love. And he is also very talented for stripping down his playing to comp so that the other artists gets in the spotlight.
And just listen to the song "Miles Beyond" by Mahavishnu Orchestra, isn't that just the greatest Rhodes riff of all time?
Keith Emerson
Already mentioned. Nuff said, incredible player!
T Lavitz
I don't expect that many of you have heard of this guy. He played with the Dixie Dregs for a little while.
http://open.spotify.com/album/29wrVgEIgi5a369BeenxGB
I'll just post this and let the album speak for itself. It's probably the most interesting and funky things i've ever heard someone do on a piano!
Eldar Djangirov
All right, he is a virtuoso, and incredible technicall. But his compositional skills are remarkable.
http://open.spotify.com/album/3HJiiBxb5ncdwHvP4mGon9
Dave Stewart
Crazy player! Love his style, his sound and rythmics. So many great melodys and riffs!
Others worth mention are:
Herbie Hancock
Joe Zawinul
Rick Wakeman
Ståle Storløkken
Bob James
John Medeski
and many more!
As for Jordan Rudess, can't really say that i like him. He got great skills but his composition are rather lame and uninteresting (my opinion).