Lucid dreaming
I've hit on this subject before, but I just remembered that I had a lucid dream for the first time in the last couple of weeks. I remember Jason G. saying that he had done it before, but I'd never actually had control of my dream-like state ever, and I vividly remember being able to shift around my perspective and move how I wished. It was incredible: no dream remotely compared to it, but I can't remember much of it at all. I'll have to figure out how to try to induce that again sometime (and whether I should).