For fans of quirky Japanese games (in English), Rhythm Heaven is half-price on Amazon today.
None of the other DS deals catch my eye, they're either for games I would never play or they're such a small discount it's not important.
PC-wise, Dragon Age: Origins is $15 off, and that's probably a Christmas gift for me.
GameStop has some big deal on used games which might matter if I were in the US but I'm not. Also Phantom Hourglass on sale but... if you're into Zelda, how can you not have played that yet? :)
BestBuy apparently has Assassin's Creed and Bioshock for the PC for $5 each, which again might tempt me if I were actually in the US.