[quote name='yukine']PocketNES? How is it? I've been using nesDS and it works pretty damn well.[/quote]
I have no means to run DS homebrew, so I haven't tried nesDS. My information may be out-of-date, but last I knew, nesDS didn't have savestates working perfectly yet (a MUST for me), and couldn't play a certain sound channel (sampled drums in Mario 3, for instance). It does have more screen-real-estate to work with than PocketNES, which must be nice. Please correct me if I'm wrong about any of this.
PocketNES is a near-perfect solution for me, mostly by virtue of being a GBA program. This means I can start a game of Castlevania II at home on the Game Boy Player, savestate it at any point, then take it with me anywhere on my DSL or Micro. Two-player games are as easy as pluging a link cable into my old SP, and if you've got the hardware handy, PocketNES supports up to 4 players.
Was faced with a lot of downtime at work once. Luckily, I had my SP, my old Afterburned GBA, a link cable, and PocketNES. Me and a co-worker sat down and beat Contra. For my money, it doesn't get any better than that
PocketNES is a commercial-quality program (and in fact has been used in some commercial GBA products) in virtually every respect. But (and I may be wrong) I don't think the MAX Media Dock can play GBA homebrew, only DS. So, Yukine, please tell us how nesDS compares, as it's probably the best (and only) option for prospective MMD buyers to play NES games on the go.