To retouch on the GBA thing - my sister-in-law showed up with a new GBA this weekend and a 40-in-one Game Boy Color cartridge for it. FORTY in one I said? Like WHAT forty? There was a bunch of stuff like Harry Potter and Wario down to Asteroids - basically a mix of GBC and original GameBoy games. She bought it at one of the "flea-market"/"swap-meet" markets while she was on vacation in the Canary Islands a few weeks ago. She paid like $30 for it.
The QUALITY of this thing was what was so amazing. It was housed in an official plastic GameBoy cartridge, with a sticker on the front that looked JUST like a real game, with little pictures of the games in a circle. The only clue that it wasn't a real product was the cheezy font face (like cartoon or brush-script) they chose. The cartridge starts up with a menu where you can choose the game, then launches it. Pretty detailed stuff for a pirate operation. I'm going down to the Rastro next week to see if I can find me one these things!