I can't lucid dream on command, but there's been 3 instances in my life where I've realised I was dreaming, all when I was a young child. I started flying in one, shouted "I'm in a dream!" repeatedly in the other, and I can't remember about the last one.
Well last night (I think this was during a dream), when I would shut my eyes to go to sleep (dreamception, I know), I would instantly go into lucid dreaming. Also, I had sleep paralysis, but in my dream. My mind woke up, but my body was still asleep, and I eventually got all my muscles moving, but this was all in my dream. I'd been looking into lucid dreaming yesterday, so I guess that's something to do with it.
During the same night, I had a dream where down my road there was this shop/place that sold cubes, and also allowed you to officially do averages. That would be a good idea IRL, if enough people went to it.
Also, when in a lucid dream, is it possible to remember stuff from your waking life? Such as what food you had for dinner that evening etc.