I don't generally have classic nightmares. But I actually had one the other night. Standard restless night dream that keeps shifting. Toward the end I was working at a hardware store or something and I was trying to get promoted. Then I was driving somewhere in the borrowed mid '80s F-150 I had and the guy who was riding with me was no longer my vaguely defined buddy. He was much larger and covered in a blanket or something. When I tried to figure out what was going on, he jumped across the cab and onto me. About the time I was going to see the horrible face I knew was under the cloak and he was likely to bite my face off or something, I decided to wake up. And it was just like that. "Hmm. I can't push him off or overpower him and this is clearly a dream and I don't like where it is going, so I'm going to wake up now."
That's an interesting quirk (or two) about my dreaming: I kind of lucid dream. But not really. Normal people, when they lucid dream, they fly and screw Natalie Portman and things. Even though I know I'm dreaming, I stick to the script. It would be absurd for me to just start flying, so I just continue to do whatever I'm supposed to be doing to make the dream story work. I don't know if it is an extreme Lawful D&D alignment or a dedication to improv, but that's what I do.
The other thing, which may be TMI, is I don't have sex dreams. Well, I do, but I pretty much always get cockblocked in them. On the rarest occasion, I'll get naked with a girl; once or twice I may have even got some head, but when it comes time to do the deed, the phone always rings or there's a knock at the door or some other perfectly logical interruption. :shrug: