The Amazon Nintendo DS Games 'Buy 3 for 2' Promo is still up (through November 8, 2008).

18 titles still available.

Details:

Stock-up on some of the best video games for Nintendo's DS Lite. Add three (3) qualifying games from the list below to your cart, make your purchase, and you will qualify for a free game. The game that you add to your cart with the lowest list price will be deducted from your total order at checkout. Each title in a qualifying order must be unique. Limit three per household. Taxes and shipping may apply. Promotion valid for a limited time while supplies last or until November 8, 2008 at 11:59 PST. Products must be sold and shipped by Amazon.com.

Check it out:  Amazon - 3 for 2 DS Game Promo