As a guitarist, probably Shawn Lane. As a musician overall, Steve Vai. I do not try to copy Vai's style, because so many people already do and it sounds terribly contrived when anyone but him is doing it, because it's so unique.
And a musician and as a guitarrist, Shawn Lane. Igor Stravinsky and Hermeto Pascoal (the most incredible musician that ever lived, according to Miles Davis).
I spend too much time nowadays hating on music that the only thing clear in my mind is who my influences aren't. Like Dime, Kirk Hammet, Jimmy Page... the list is endless. I focus on being absolutely nothing like these people. To me, the greatest influence is individuality. You find that by doing the opposite of everything you ever hated.