The practice of rolling up a towel diagonally, so it tapers to a fine point. This can then be used to whip people coming out of the shower.
I could never perfect the whipping action, which made it all the more surprising when I caught Francis Gotto on the end of his cock with an absolute corker of a flick. However, something (I presume a label from my towel) went flying off just as the crack (and subsequent howl of agony) happened. For a few horrid seconds I was convinced that I had literally whipped the top of his dick off like popping some sort of phallic champagne cork. Images of expulsion and/or prison rampaged unchecked through my head.
I never rat's tailed anybody again.