Strangest one I've seen (driven by a dare based on an inside joke):
Walks up to two girls randomly selected in department store: "What do you know about cccccooooorrrrrnnnnn?" (Emphatically, with "corn" drawn way out for emphasis). Turns around, walks away.
Girls giggle, look slightly confused. Then one chases after retreating buddy, introduces herself and gives him her phone number. We were dying the whole time watching this, and needless to say, that is the stuff legends are made of.
It cracks me up just remembering it. Very, very strange, and not something we were expecting to work.
Yet another good example of confidence being far more important than the actual words spoken.