Aside from learning how to play the market to make even more money, I'd buy all the little things I'm always annoyed I don't have. I'm serious, I've thought about this a lot. I'd buy safety pins, staples, push pins, sewing needles, tape, pens, etc. HA.
I'm sure I'd also buy everything off of my wishlist and more. Oh! I'd buy even more kink equipment. <3