Made with MS Paint and GIMP. All 512 x 512, max image size for marble skins. Any larger crashes the game!
Transparent versions recommended if you have environment maps turned on. Opaque versions are just there if you want to view or edit them.
Billiards Balls
(etc.)
Bumblebee
Inverted
Pokéball
Watermelon
(If you wanna know, I made these preview images in GIMP with the "Map Object" filter.)