The Serious Sam demo/test is pretty interesting. I think the one important thing it's lacking, though, is alternate firing modes for its weapons. Frankly, I can't imagine why new games are made without that feature, that's how attached to it I've become.

I have to say, though, it felt a hell of a lot like I was playing Gunslinger Quake single-player. Knife, revolver, double revolver, pump-action shotgun, double-barrel shotgun... wonder why I felt that way?