Looking for something to collect

[Beta Man]

I know it's very vague..... but I'm looking for "Something to collect" for my son.

The thought occurred to me since I'm planning on buying a lot of vintage Star Wars figures make a shadow-box type display on the wall of the stairway going to my movie room, and I don't have ANYTHING from when I was a kid......

I'm looking for ideas on things to start collecting for my son, so he can enjoy a hobby of collecting something when he's older, and perhaps to have something that will be a large and valuable collection when he's older.

Not interested in Stamps, coins, shot glasses or baseball cards..... I collected a LOT of baseball cards when I was younger, but now it seems that they are sold with expectation that people can make money with them in the future, so the market is pretty much trashed for them..... also, I'd like something a little more unique than that.....

I don't care for the mighty-mugs, but something similar perhaps??? I was thinking of something small like Matchbox cars, but I'm just looking for other ideas.... something that isn't already widely collected, so Comic Books are out etc.....

Ideas???