Jimi - even if he sung monotonously, Jimi made monotone COOL! SRV and Ace Frehley would never have had a snowball's chance in hell for acceptance if it were'nt for Jimi's sedate (or acid-tripped out?!) vocals. Awesome chop + ok vocals = still plenty of chicks ;P
Richie Kotzen - shred that just KILLS you. his funky-bluesy-jazzy style is perfect for his soulful voice. i think his guitar playing reflects his voice, i really hear the connection. musical maturity is a good thing, he's the embodiment of that truth. RK rules!
John Pizzarelli - saw him on tv a few times, and his scat singing on top of his sound-barrier-breaking bebop lines makes you freeze and think about why you should even continue playing guitar. for a while i considered calling it quits and taking up something else to find musical solace and deep expression, like the glockenspiel, triangle or egg shaker, and be cutting edge with it. even to the point of finding a new hobby... fishing or toothpick architecture, anyone?