I have actually heared that you can link up your GBA to the wii's Gamecube port and play such games as Crystal Chronicles and various others as if it was a Gamecube and not a wii. I do not know if that is true or not, but it seems pretty cool.
I wish Nintendo would allow some kind of adapter for the wii that allows you play all the GBA games on that console. Basically, something like the GBA player for the Gamecube, but it would be smaller and would plug into the USB port on the back of the wii. I imagine Nintendo would have to release some kind of Gameboy channel via firmware update, but it would not be too hard on their part. They could also relase an adapter that allows the GBA gamcube player to plug into the wii's USB port, but this does not seem pratical for Nintendo to do.
I actually have Tacics Ogre: Let Us Cling Together for the GBA and no way to play it. I sold my GBA ages ago, I do not have a DS Lite ant more, and I sold my Gamecube and and the GBA player as a down payment for my DSi. I am up **** creek without a paddle and I refuse to rebuy any of this hard ware to just play a handful of games.