For me it was Station Approach by Elbow [0] - the one with the giant slow semibreve vocoder chorus [1]

Not obscure at all, but i sang it to bemused twenty-somethings in a dozen record shops. I had high confidence from the timbre it was Super Furry Animals, so i also combed their catalogue. In the end i bought the album blind (deaf?) on a recommendation and was gobsmacked to find the track on it. Serendipity, baby!

[0] https://www.youtube.com/watch?v=q2k5EfLPB3A

[1] all this time, i thought it was a vocoder! I was just listening on crappy speakers, i guess. It's just tight vocal harmony and a production that possibly puts the bass through the vocal reverb

That video is something else, wow.