Mine would be back when I was in my late teens, we were partying at my GFs house, had traded 30 hits of VERY good white blotter for some good pot, my best friend at the time and I were on at least 10 hits of this acid each and we smoked a shit load of this pot, it all started to get weird when we were passing this joint back and forth on the side of the house, suddenly GFs cat jumps down from the porch, it literally had sparkles all around it, we both saw this too!
So we end up back at my friends house, by this time, he was going into a bad trip, was pacing the floor in his house, (his parents were asleep in the house too), so he calls 911, but hangs up, well, cops and emts show up 10 min later anyway..they strapped him down and took him to the hospital, and were fucking grilling me and this other guy with me, asking where the rest of the acid was, luckily the other 200+ hits were safe at my GFs house along with the pot.
The funniest/ scariest thing that night, when this cop was grilling me, I kept seeing his words come out of his mouth and float around his head, like comic strip bubbles LOL They eventually let us go, nothing they could charge us with...my friend got out of the hospital next morning, we joked with him and dialing 911 and hanging up and awhile after that too. We think the pot was laced with something, I have never had a trip like that before, or ever again after that.