I've experienced deja vu only a handful of times in my life, but the feeling was so strong that it's hard to just blow it off as some "glitch" in the brain. Mostly my experiences came in the form of over-hearing a conversation between two people, and knowing in advance what each of them was going to say. Also I've had the whole knowing a song even though it was new and I had never actually heard it before. Very unnerving.

I don't know what deja vu is, but it certainly is something I would love to learn more about.