Which DS game has given you the most value for your money and time?

[DKII]

MarioKart DS, Age of Empires, and Final Fantasy III. I never got Advance Wars but I'll pick up the sequel when it comes out. Putting a lot of time into Pokemon right now and I'll be picking up Picross at some point which for $20 and infinite puzzles I think I will be playing for a long, long time.