When something is so beyond your normal day-to-day experience, your brain tends to get overwhelmed. That's essentially what I think happens when people say some event felt so "surreal". That's exactly how I felt on 9/11 walking the streets of Manhattan. I was scared on the inside and also kind of disoriented, but I think I looked like a Zen monk on the outside.

Even with a video clip two years after the fact and basically knowing what to expect after having watched many other tsunami videos, my jaw still hung open the first time I watched the full clip and saw what the power of a tsunami could do.