I've only used three of these, but they were great. I had Contra, Halo 2, and Mario Kart 64. The others look sweet though.

used all of them except the doom and contra ones, I really think the GG should be 2nd and the scorpion gun from halo2 should be 1st, but I guess you had to "cheat" to get it so I understand

The one I definitely agree with was number 1. The gravity gun was so much fun especially on multiplayer, clobbering people by sending a table flying at them was classic.

Holy crap, I actually remember the BFG (#3) from my time playing Doom on DOS O__O'

It was funny seeing the red shells from Mario Kart in there at number 2.

Well, if you've played MKDS, Red Shells is the best weapon out there XD.