When taking acid for the first time, I drop a tab with my friends, and we waited for things to kick in. I wasn't feeling anything, after about 3 hours or so, so I took a 2nd tab, just as they were starting to peak. About 5 minutes later, my first tab kicked in, and the 2nd was a few hours away from joining the party.
Short version, I had a very long, very manic night. I saw a poster of Libra by Susan Sedon Boulet warp and shift like crazy, which included a little squirrel under the poster woman's blindfold. The squirrel peeked out to look at me as if to say "Yep, you are officially tripping balls now." And then scurried back under her blindfold. The wall that the post was on, was pulsing in and out like it was a chest that was breathing, and it was in time with my oscillating fan on my desk. Light from outside, was coming into my room in visible waves, like I could literally see the rippling pattern the light made. It was winter, and I had to go to the 24 hour store for stuff, and I had to defrost my windshield. The melting pattern, backlit by the amber lights of the school parking lot, melted out to spell "Mushroom-arama" on my windshield. Let's see, what else.
I could see new stars exploding into existence in the night sky, and spent hours stargazing as a result. I also kept feeling like I was flying whenever I went up a flight of stairs, so I started running up and down the stairwell in my dorm multiple times...all 7 floors. A bunch of other things, that ended with me imagining one of my friends at that time in a car accident after she dropped me off, because she was tripping too. The only way I could distract myself from the bad trip at the end, was to read The Fellowship of the Ring. And while tripping, I was FINALLY able to sit through that boring fucking book, and finish it. For years prior, I could never finish the book, because it was just so damn dull. But, with the help of a brain full of LSD, I was able to lose myself in Middle Earth and finish the book. By the time I finished the book, the drugs had worn off and I was able to sleep.
That's probably the strangest single thing overall, though there were other drug related events that had some significant things to them, but were less intense from start to finish.