This one actually got pretty trippy at the end, but it just started out stupidly. I was in high school with the Buffy gang, and we were taking a field trip... by plane. On the plane I sat next to Buffy and we talked about how we would doubtless have to fight some stupid monster on the field trip. Well, I can't actually remember what the purpose of the field trip WAS, but somewhere along the line Xander and I (because this kind of thing ALWAYS happens to Xander) somehow pissed off a tree spirit or faerie or something. (It was a small woman with wings... who looked vaguely like Sumomo from Chobits, actually.) She cursed us. Then we left. ^_^*
Later on we were at someone's house when the faerie-woman came back to fulfill the curse. So Xander and I spent a long time trying to run and hide from her. Eventually, though, she caught up to me, and what happened then was the really trippy part. I fell forward onto my face, and a bunch of flowers and plants grew out of my back. It really hurt, but they just sort of dissippated after that, and I was fine. I'm not entirely sure what the purpose of it was. Xander was a bit less lucky than me - an entire tree grew out of him, and it looked a lot more painful.
Man, that was a weird one.