You are exposed to relatively high doses of radiation from the time you go through security to the moment your plane lands.
Chances are you've heard a description of what's called a near death, out-of-body experience. For a lot of people, it's a powerful, even mystical experience.
For people with REM sleep behavior disorder, or RBD, the action in the dream is acted out in reality!
Almost all mammals, in fact, have REM sleep; birds do too, although only in the early parts of their lives. It seems that sleep and REM are required by a particularly complex kind of brain.