I've wanted to try out doing improv theater for over ten years, despite not being a theater person and despite not being particularly dramatic or even extroverted. I finally went over the weekend, due to the encouragement and participation by my girlfriend.
It's pretty fun, and very different from anything else I've done. For some reason I had thought I might be good at it, but there wasn't any evidence for that during the 2-hour class.
It's a little disturbing that the easiest exercise was the Status Game - you pair up with somebody, and each of you get 3 playing cards that you're not allowed to look at. You start improvising a relationship, say two people fixing a car. Each of you put a card on your forehead whose value denotes your status level, you can't see your own card but you can see the other's, and you both switch to one of your other two cards at random intervals. You then improvise your status relationship based on the other person's card and on the signals you receive from the other person about your card's status level. It was really interesting, but we humans are disturbingly good at hierarchies.
I'm glad I did the class, but I'm not sure if I'll pursue it further.