Just to add to the general pool of knowledge on this delicate matter following Kit's legendary thread t'other week.
This morning, on the London underground, I actually witnessed a young man perform the following. Standing in the middle of the carriage, he removed a battered Moleskine notebook from his bag, selected a blank page, and wrote (in a flowing, confident hand):
Don't you hate the way people don't talk to one another on the tube?
[cell phone number]
He then tore out the page, carefully folded into quarters and placed it in his pocket.
Sadly, I left the train before I was able to witness the handing-over of the note, and I am not therefore able to pronounce on the degree of success that accompanied the move.
Has anybody (other than Houns) actually got the balls to do this in real life? I was slightly in awe.