Tom Morello is my fave overall just because he can get more out of a guitar and effects than anyone else.
Herman Li (DragonForce)
Joe Satriani
Yngwie Malmsteen (I really don't like this guy, but he is good at guitar...)
Blake Sennett (Rilo Kiley. Not the best at all, I just like his songwriting and playing style)
Dave Knudson (Minus The Bear. Way technical)
I don't really feel like listing too many more... Minus the Bear is awesome.