Oh, and another interest (although I won't say obsession really) is dice. DS5 loves dice. We went and got him dice that has all different numbers on them (like ones by 20's, and different shapes, etc.) He thinks they are the coolest things. He makes up his own games with them.
Our DD also. Her daddy is a gamer, so she's been interested in them forever. She especially likes dice of unexpected size. She has some that are very tiny and one inflatable die that is huge. :-)
I had a similar thing with playing cards as a teen. I liked huge playing cards, tiny ones, round ones, etc. I still have most of the decks.
