The Wiibrew scene just seems to be exploding with emulators. This one comes from developer nullEX, and is an emulator for the Game Boy Color. It's a remake or mirakichi's RinWii emulator, and so is aptly called the RinWii remake. The program is now on its second beta, which now supports loading from the Front SD. Be sure to read the documentation before you install the program. Here's the readme:

- uses GRRLib for drawing
- uses the last cvs libogc
- compiled with devKitPPC r15 from cvs
- wiimote support using "wpad.h"
- frontsd load/save using libfat from cvs


Buttons:
- Menu
. move your wiimote and select by pressing A button.
. Home buttons exits from emulator.
- Game
. In Horizontal position
. 1 -> B
. 2 -> A
. - -> select
. + -> start
. A -> start
. HOME -> Menu
. B -> change screen size


Folders(you must create it):
. Roms -> /roms/GB
. Saves -> /savefiles/GB