SDL MAME Wii (official Release link) 0.4 released by Toad King:
SDL MAME Wii is an Arcade Emulator based on SDLMAME. Many games for early arcade boards can be played with varying amounts of success.
Issues
Lots of ROMs are supported, but not all of them. If you don't see the ROM in the list in the emulator, then support for that ROM isn't included. This is to keep the size of the emulator low enough to run effectively on the Wii. A list of all the ones that are can be found here: http://www.toadking.com/wiimame-0.4.txt
Just because a ROM is supported does not mean it will run. Even games for early boards like CPS-1 can fail to run due to RAM limitations. If the emulator suddenly kicks you out to the Homebrew Channel, look in the MAME folder (sd:/mame/) for a file called errors.txt. If it says something about failing to allocate space, then odds are the ROM can't run on the Wii. The emulator might also crash outright and leave you with a code dump if RAM runs out.
Only software rendering is supported. This makes playing games without using the frameskipper slow, but the auto-frameskipper feature is enabled by default.
The joystick on GameCube controllers can't be used.
The default UI font is way too small. A custom font is included, called Helvetica LT. (http://mrdo.mameworld.info/mame_artwork_supp.html)
The default controller mapping is unsuitable for lightgun games, but there is currently no way to make seperate mappings for lightgun and non-lightgun games. If you wish to change the configuration for lightgun games, replace the default.cfg file in mame/cfg with the default-lg.cfg file included.
Changelog
0.4 - November 24, 2009
Upgraded MAME to 0.135
Added WiiMote Sensor support
Stereo support fixed
Game list now shows up to 150 ROMs instead of just 15
Changed USB/SD detection (Tries USB first, then falls back to SD)
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