Outside my flat in a (studenty, but quiet) area of Edinburgh a few weeks ago. At 11pm on the dot someone starts playing bagpipes at full volume (is there any volume control on those things?), and gives a wonderful rendition of some tune.
Immediately after, several people from the surrounding flats start applauding, a couple of people cheer, and after about two seconds someone clearly articulates the word “wanker”.
What makes this perfect is that he waited until the performance was finished before shouting out—it would have been so easy to have shouted it in the middle, and so less effective.