I have two.
1. A hotel close the the airport in Honolulu. We got in late from California, and had to stay the night before catching an early flight to one of the smaller islands (either Molokai or Lanai - I forget now). The hotel itself was OK, but there was a nightclub right.next.door, and the loud, thumping music didn't stop until 4 AM. It took me a couple days to recover from the trip.
2. A hotel in San Luis Obispo. We were up for a work-related conference, and I had arranged lodging for about 15 of us. When I made the reservations over the phone (this was before internet hotel reservations), the guy assured me that all of the rooms had 2 beds, which was important, as I was putting 2 students in each room. We pulled up, and I asked the guy at the front desk the same question, mostly because the guy on the phone sounded a bit skeevy. The guy hemmed and hawed and didn't really answer. Then the other guy, apparently the owner and the guy who had been on the phone, came up, and said that, no, the rooms had only 1 bed. Oh, and the town was full, so too bad, so sad. He'd lied, what was I gonna do, sue him? Needless to say, I packed everyone back up to find a new hotel, despite one of my coworkers whinging that we could put up with this, it'd be OK. Well, I wasn't going to put up with being duped, so we left. We found a decent hotel, who didn't lie to us, and for about the same price. These days, I'd've left a scathing review everywhere I could, but that was no option back then. It *still* makes me mad!