I too love the flak cannon in UT, dual pistols is also fun.
UT really has a lot of great weapons, I liked the razor gun too, was a blast to decap many enemies.
Old skool though ? Would have to be the airhook in quake
It was great to hang in a corner with the rocket launcher, or pull-frag, just a great tool more then a weapon I guess.
My current favorite would have to be the Apache in BF1942 : DC
