CustomGameCovers has a cool product for Wingnuts who own Prophecy for the Game Boy Advance. Since the game comes on a cartridge, it's very popular on the resale market - although it's commonly without a box. This solution fills that need with a reusable DS-style container that has a slip cover based on the game's original cardboard box. It's not really a collectible piece itself, but it could be a nice complement to the Prophecy Advance in your collection! You can order them for about $10 on eBay. There's also a deal where you can buy two and get one free.