What's the weirdest piece of merchandise you own.
As for me. A pillow case.
On the front is Ash and Pikachu. On the back, in the center, Pikachu, and in each corner, Clefairy, Meowth, Squirtle, and Polliwhirl.
I also made a t-shirt with pictures of all 493 Pokemon on the front. On the back it lists them.