I want to, but the idea of nerds more hardcore than myself intimidates me a little.
But my sister went to Wizardcon in Philly and paid Peter Mayhew $20 to sign her illegal copy of the Star Wars Christmas Special. He didn't say anything to her, but she said he looked annoyed until she told him "I have money."
I don't know if it's true. But it sounds like something she'd do to a celebrity.