there are some great heavy single coil tones out there - the who, led zep, sabbath
Erm.... Townsend - Gibson Les Pauls, SG's - humbuckers
Jimmy Page - Gibson Les Paul 1958 - humbuckers
Tony Iommi - SG's - humbuckers
May I add:
Clapton - Bluesbreakers, Cream - Les Paul's, 335's - humbuckers. He used strats post-burn out, watered down his sound
Jeff Beck early days - Oxblood Les Paul - humbuckers
O.K., you may play the Jimi Hendrix card - Marshall stacks flat out, Roger Mayer effects to fatten the tone
Stevie Ray Vaughan - really high action, 13's to fatten the tone
(Don't you dare play the Rory Gallagher card - I have no explanation. Huge tone, masses of balls with a simple strat through AC30 set up. Just a huge spirit and serious Irish manliness to fatten the tone. Genius.)
Single coils do great tones, but when you want beef you either use humbuckers or use modifications to your single-coil set up. For the best representations of what single coils do we turn respectfully to Nile Rogers and Hank Marvin. Both fabulous players, thin sparkly tones that work very well for them.