My HS has some pretty interesting one. See, I was sitting around on the 2nd floor one fine day, when lo behold, a figure flew down past the window just outside. After screaming like a girl, I found out it was a bunch of students doing a climbing exercise outside for P.E.
And once at my college, a bunch of us were really exhausted after working until well past midnight in a computer lab. Then suddenly, the computer started typing by itself, responding to our conversation in part English, part jibberish. Turned out it was the voice recognition function acting up. But damn, it was creepy as hell, since it was just English enough to pertain to our conversation, but clearly not what any of us had said. (It probably combined a lot of our responses to each other together)
