What do you collect?

Chinese cash. Not the paper bills that we associate with "cash", but the quite old and mostly copper/bronze cast coins that were used in Southeast Asia from the BC period up until the 20th century. I've a few thousand of them ranging all across that time frame. They are pretty cool in that you can generally find out who they are attributed to regardless of their age. Back in the 1990's it was pretty niche but easy to find them cheap. Now it seems Chinese collectors have stepped up their game and made them harder to get, or at least driven the price up.