Video game bargain bins.
"PS2 games under $5!? You kidding me!?" *spends hours and hours and hours digging through thing thing looking for gold*
Actually, just bargain bins, in general. Being a bit cheap, there is nothing like seeing things I couldn't get a few years ago, now for a price I can't help.
Forum debates/arguments about personal perspective, too.... well, umm, more telling people that they shouldn't be placing their concepts of X on others simply because they think X and giving reasons to this... as well as making sure the unrepresented minority gets made aware of. I don't know why, but I like it. O.o Especially in terms of writing ability and capability.