Guitar Heroes

Upon hitting one's distortion pedal during a stage performance, one should give the appearance that the guitar has suddenly and unexpectedly become difficult to control (not unlike a bucking bronco). One should appear suprised by the sudden increase in gain and in the best case, one's hair would stand on end.

The best example of this is Jack White during the Fell in Love with a Girl / Dead Leaves and the Dirty Ground medley at the 2002 MTV Movie Awards.

Additionally, one can feign suprise anytime one hits an artificial harmonic.
See : Multiple guitar heroes.