I'm in the process of doing 1, have maybe done 2 depending on your definition of aggressively (made only a couple donations, but largest was ~$1000), and done 4.

Oh, and 11, I got Amazon Prime on Yvain's recommendation, and started taking melatonin on gwern's. Both excellent decisions, I think.

And 14, sort of. I once got talked into a "polyamorous relationship" by a woman I was sleeping with, no connection whatsoever to LessWrong. But mostly I just have casual sex and avoid relationships entirely.