Sadly none. I can't seem to bring myself to finish a game. I like to try all the games NDS has to offer. The ones I play the most are usually games I can just pick up and play for 10-30 minutes. Usually puzzle games.
I know what you mean, I can't finish a game anymore no matter how hard I try. On Wii I got to Ganondorf's castle and just stopped. In Pokemon I got the 5th gym badge and stopped, etc. It sucks.
I'm the same way. I get tired of things easily so i will get tired of a game and plan on coming back to it later and I never do.