It must have been exciting to be a music fan in the 1960s, as there was an "anything-goes" mentality with record pressing. I have found records with yodeling, honky-tonk, children's choirs, puppets, and cricket recordings and they all seem to have been released willy-nilly into the atmosphere with no idea of sales, target audience, or financial concern.
One of these funny experiments was made by Wendy Carlos, an accomplished pianist who had an unusual curiosity for the emerging Moog keyboard. Unlike the average wanker, she approached it as a legitimate instrument and made layered recordings of classical compositions, in which she played all of the parts on a differently-styled Moog patch. Surprisingly, they were such a success that she was able to make four different albums.
The Well-Tempered Synthesizer may be one of my favorites since she had honed the process at this point. There is a bit wider range, so that she was branching out from Bach to include Scarlatti, etc. They somehow sound timeless ("classical") and futuristic at once. I can't think of anything happening today that still sounds this fresh.