While I did like N64 back in the day, I think my all time favorite has to be the 3DS.

Why? Well, because I'm legally blind (20/200 vision uncorrectable). The 3DS XL is so far the only hand-held system that I can see to play without crazy huge magnifying glasses. I still have to strain to read certain text at times, and I have to hold it about 2 inches from my face... XD But for the most part I can enjoy a game comfortably. That thing is kinda heavy, though. Gotten more than a few hand cramps. XP

Anyway, aside from that, it's also a system with some pretty great games. I've enjoyed most titles I've purchased for it so far. :)