Goomba is a Gameboy emulator for the Gameboy Advance. Beyond the advantage of being able to store many games on one cart, Goomba also includes save states and customizable borders. At least, Kuwanger’s fork does. Also available are many palettes, along with the ability to make your own. This feature has lead to the creation of a small gallery, for your viewing pleasure, see

Release notes:

Goomba Paletted v2.34 – 2009-04-20 – Support appending palettes to goomba.gba