My babysitter took all of her babysittees (including me) garage sale hopping one summer. That was kinda cool. I haven't really gone to many other than that which I can recall.

My parents had one some years back, I got rid of a few toys... didn't make much cash off it though (like $10).

Dad's always taken me to flea markets and stuff which is basically like a garage sale so it's sorta similar.