I hit my gym. I discovered many things can be solved in a gym. You know when you want to hit someone? Aim for the person you hate most in the gym, even if you don't know them. Pick up 2 120 lb dumbbells, and try. That'll get your anger out of you. And the person you were aiming at might think of you as either constipated, or very angry and run.
Sorry, that was my example. Everyone's got their limit. And comeon, once you've strecthed your back, you'll have a new worry for around a month and a half until it heals =)
Drink lots of water... talk to my friends... play computer games... I would try and exercise when I am stressed, but by the time I get properly stressed, I probably haven't actually slept properly for a week and have a really bad headache, so exercise isn't really on my mind!
I have learned a technique, which I tested and very useful for me. If you like, you can check my website for that technique
I smoke cigarettes when I am stressed out, It really helps me coupe with certain stressful situations.