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.

Release notes:

2009-10-21 – Support up to 256 borders and 256 palettes. Adds a list for border/palette selection (modification of Dwedit’s list in Goomba Color).

http://kuwanger.net/gba/goomba/