When I was a kid I used to have those blue books that you put pennies in, like each year had a slot for a penny.
I guess that's run collecting in the coin world.
What was up with those ads in comics that said, "If you have this penny it's worth $100,000." ? And they had catalouges you write for. I know it's off topic but I just got up and I've only had two cups of coffee and the dog mess the floor.
EDIT: just looked it up. they were called "Whitman Albums." Did they make the Whitman variant comics, too?