The GCN homebrew scene isn't exactly booming, but there's now a fully-functional SNES emulator touting high compatibility (all special chipped games included), 4-player support, and SRAM support.
http://gcemu.dcemu.co.uk/snes9xgx.shtml
The only items you need to get this working are: Nintendo GCN SD Card adapter, Action Replay, and of course an SD card. Since the SD Card adapter is quite rare now, you can acquire a perfectly useable homemade one from this forum --> http://www.gcdev.com/phpBB2/viewtopic.php?t=1493&start=30
http://gcemu.dcemu.co.uk/snes9xgx.shtml
The only items you need to get this working are: Nintendo GCN SD Card adapter, Action Replay, and of course an SD card. Since the SD Card adapter is quite rare now, you can acquire a perfectly useable homemade one from this forum --> http://www.gcdev.com/phpBB2/viewtopic.php?t=1493&start=30