Thanks to Matt for sending this mod in:
I gutted my old Nintendo, put my Wii inside, installed some fun LEDS controlled by the original Power button, replaced the controller ports with Gamecube ones, stuck a Gamecube memory card inside, spray painted it, etc etc. Well, it was worth the hours I put into it and I was hoping you’d post my Youtube video I made for it up on your site. I’m planning on writing some detailed instructions on how to do this, but its much more complicated than you might think due to the space restrictions inside the Nintendo (cutting off parts of gc extension cords connectors as well as cutting all that excess cable and resodering them, cutting a hole for the memory card, shaving one of the four supports so the card fits in, dremeling almost everything inside the original Nintendo, etc). Believe it or not, the Wii can still be taken out of the Nintendo if unscrewed (ie if you need to sync some new wiimotes, or access the sd card slot.) The eject button is available via a small hole in the front which can be poked with a paper clip just like an old floppy disk drive.
http://www.youtube.com/watch?v=jTs8c4r8m94