Ya exercise definitely makes me feel good. But you're right it has to be an intense kind.

My wife and I have been training in martial arts for over 2 years now and so far nothing has matched the intensity. We have a private class with an expert who also fights and the sessions nearly always leave me on the verge of passing out. We feel awesome albeit exhausted after.

For sex, who can argue? It's definitely great. Though I'm lucky to get once a week in (with a 4 year old in the room). Haha

I've tried fasting as well and I concur. I feel more calm and mellow. At the start tho, you may feel irritable and snarky - cause you're still getting used to coping with hunger.

Other things that help me are comedy (funny shows) and music (guitar etc...).