What’s a signature worth?

I’m somewhat fascinated with the idea of autographs, and why people will pay a lot of money to get a famous person to sign something like a photo, baseball or napkin. I guess it’s a cool piece of memorabilia, completing a “thing” that one would collect — and maybe daytime proof that one met someone who’s only seen in People. I came across this rundown of autographs at the upcoming Comic Con — and I’d probably head to the Comic Con to meet Michael Biehn for $30. It’d be worth it to say hi to Hicks from Aliens, though I probably wouldn’t need his autograph. Unless he made it out to Sandy.