I've had it once - I dreamt I was jumping off a waterfall and when I hit the bottom I was underwater for what felt like hours - I woke up panting for breath so damn hard it took about 30mins to get my heart rate back to normal. At the time I didn't know that it couldn't be fatal, so I didn't sleep for 3 days after that, I was scared that I might have the same dream and die...

Now I know different but like you said moeburn it still sucks.