I don't think I'd have the chutzpah to do what Greg Benson does here.
From Gawker.com: The Perfect Solution to Obnoxiously Loud Public Cellphone Conversations
And the "outtakes":
Ouch!
History, Religion, Epistemology and Communication with a little Politics, Economics and Legal Theory thrown in for good measure. Plus . . . whatever strikes me as interesting or humorous.