DS DS DS DS DS DS DS DS.
I always have my DS Lite on me, and usually one of my GBAs so it doesn't get dust all over it after wood shop (won't have to worry about that next year). I just got an M3 DS Simply, too... I think it's safe to say that it lifts it even higher above the PSP: it can play MP3s (mehh, I have an iPod mini), videos, and virtually any DS ROM with full functionality (yeah... I still will buy games though). I also have nesDS with which to play NES games, SNEmulDS to play SNES games (limited compatibility and still a bit glitchy and beta-y, but enjoyable). I'm really let-down that SMRPG cannot now and can probably never be emulated on the DS, because you can't have that chip whose name I can't recall, but I have Tetris Attack. I've also got a sampling keyboard on it, and an IRC client.
So, er... you were saying, about the PSP? If you add the cost of the M3 DS Simply, the 1 GB microSD card it uses (mind you I found an unbelievable deal on that card), and the DS, you've got about $190's worth of pwnage... how much are PSPs selling for these days?
Lots of parentheses.