Toys, toys, toys!
I have so much fun when I visit Tokyo, but my favorite thing to do by far is explore all of the toy stores. You can spend hours and hours in toy stores like Kiddy Land and Hakuhinkan just tripping out on all of the cute (and bizarre) toys.
Luckily I can browse Rakuten's english site for cute Japanese toys. Rakuten is a huge online shopping site in Japan--their english site is kind of hilarious because everything is just ran through a translator. Check out this listing I found for a 'worn-out, exhausted plush leopard'.
Have fun browsing, fellow toy enthusiasts!