Man, I used to use Game Maker alot. Although, I don't think I ever got a project finished, the second I hit a little thing that I didn't know about was the second I started a new project.
Still, I had some nice top down shooter games (by games I mean couple of unfinished levels with nothing but placeholder art), and I did build an FPS engine which one of my friends used to build a game that was like a farm, and you went into the seperate pens to kill the animals (all the animals being monsters from the original D00M of course).







