And by now, I don't mean right this minute. Which one are you currently working on/trying to beat. For me, having just finished Half Life 2: Episode 2
Battalion Wars - GC
Mega Man 3 - NES
I try to limit the games I play to one (somewhat) new game and one old school game. I jump from game to game too much to do otherwise. I have the feeling that even tho I am at the 4 levels after you beat the first 8 bosses on Mega Man 3, I will still be trying to finish it for a long time. Those guys are harder than usual for Mega Man games.