Masturbation. I mean, not to be disgusting or anything, but physiologically and anatomically it is proven to be.
Other then that, playing video games helps. inFamous with its sandbox and CoD4MW1 since I have the slow mo, unlimited ammo, and tire cheats when I shoot someone. there's nothing funnier then when a guy comes around a corner and I pop him before he knows what hit him and he explodes into tires.
Grunge music and alternative music helps me. No matter whats going on
<spoiler=These two songs always make me feel better><youtube=YEvVIgCm1zg><youtube=ODTv9Lt5WYs>
Always make me feel better.
Plus a good old game of street hockey with friends helps. No big huge hit him so he cant get back up and move hits, just some nice shoot and see how much you score. The kinda games that end with 38-31 scores.