Back when most everyone listened to music on vinyl, frequently switching between 45 RPM 7" platters and 33 1/3 RPM 12" albums would mean that eventually, you'd forget to flip the speed selector switch on your record player and a song would come on at the wrong speed. Sometimes, it sounded right. Occasionally, it even sounded better. Eventually, experimental musicians would go on to release records meant to be played at any speed and DJs would incorporate wrong-speed songs into their sets. Over at In Sheep's Clothing, enjoy a collection of pitched up and pitched down songs including my favorite example of the genre above: Dolly Parton's "Jolene." Below are a couple others with In Sheep's Clothing annotations. Check out the rest here: "When Wrong is Right: A Collection of Classic "Wrong Speed" Records"
ESG – UFO (1981): An absolute B-Boy classic, early NYC Hip Hop heads clung to the funky breakbeat rhythms of Bronx outfit ESG and found gold when they played their UFO single at 33. It caught the ears of RZA, who made it a live Wu-Tang staple. In doing so, they tapped a sound that predates the sluggy, bass-driven DJ Screw chopped-and-screwed motifs to come. UFO eventually became one of the most sampled songs in hip hop — and was even pressed at the wrong speed when it appeared on the classic 90s "Ultimate Breaks & Beats" comp series.
Azymuth – Jazz Carnival (1979): This '79 Azymuth hit was a worldwide club favorite, especially at Chicago house and UK dance parties. Only in Italy would you hear it played at 33, where [DJ Daniele] Baldelli had a knack for playing what was hot at the time in a new and clever way. It often resulted in a full-blown freakout on the dance floor.