You know, it has never happened, but I have always told myself that if I ever end up seeing an artist of some sort (actor, painter, musician, writer, etc.) that has some degree of fame and is one that I have respect for, with the exception of a select few, I wouldn't bother approaching them. Outside of the one line of "Hi. I just wanted to let you know that there is someone out there that really appreciates your work" I would really have nothing else to say to them. That one line being reserved for the before mentioned exceptions.

The uber exception being David Fincher. I would not be able to stop from humping his leg.