FCE Ultra GX is a modified port of FCE Ultra v0.98.12. With it you can play NES games on your Wii/GameCube. The GUI is powered by libwiigui.

Changes:

Improved stability
Fixed broken SDHC from HBC 1.0.2 update
Fixed issues with returning to menu from in-game
Add option to disable rumble
Auto-determines if HBC is present – returns to Wii menu otherwise
Miscellaneous bugfixes

Free and legal NES roms to try with this emulator can be downloaded from here: http://www.pdroms.de/files/nes/

News Source: http://wiibrew.org/wiki/FCE_Ultra_GX

http://code.google.com/p/fceugc/