A Wii or a 3DS! I don't quite have that yet. What I do have is an Gameboy Pocket (Black and White version) and two DS's which are, my DS Lite and a DSi.
FYI If you have nothing nice to say just keep your mouth shut!
Either the Japanese Gameboy Light or the original Nintendo DS prototype. Both are virtually priceless, more museum pieces than anything else, doubtful to be used, granted I am not a collector. Besides those items, one of those limited military-grade laptop computers built to withstand harsh environments. (Must come in desert camo.)
All things considered, I must defer to the GBA SP Famicom edition (pic). In addition to obviously selling the nostalgia, I simply find its white/maroon colour scheme ultra-appealing. And while I love black and grey on almost anything, neither fits the essence of an SP. It's one of the few elusive electronic items I seriously hope to obtain before it is too late. An NDS prototype model would be a luxury whim, and this is neither. Advance Wars and Castlevania beg for this model.
Dude, I wish I still had my old Dreamcast from back in the day. Along with my old Neo Geo Home System that my dad bought me as a kid. I played the hell out of that thing.
If dysfunction were a hammer, I'd be hitting myself with it.