Nintendo is comming out with an adapter for the system that plays all GBA games on your TV screen.

http://www.planetgamecube.com/news.c...n=item&id=3703

Of course you have to shell out an adittional $50 or something, its about $20 cheaper than a GBA unit. It is comming out to the US. The official press release of course:

http://www.planetgamecube.com/news.c...n=item&id=3704

If you have a GBA to GCN link cable, you can use your GBA to play the games that way, or use the Gamecube's controller.