GBAtemp.net - The Independent Video Game Community

Supercard DSTWO does DS and GBA, any card can emulate GB/GBC. If you don't want to emulate GBA (which the DSTWO does, not 100% accurate) you can get an EzFlash 3in1 or EZFlash IV in addition to any DS Flashcart to run GBA roms on hardware if it's a DS or DS Lite. Perfectly accurate (same as running real game) but a little more expensive and not as seamlessly integrated.