Digital Compact Cassette - another Philips failure
Excepting the CD-DA, Philips really knew how to make rubbish technology, and the Digital Compact Cassette was a doozy. Launched in 1992 and finally killed in 1996, it managed to take a number of audio-equipment companies down who'd believed in Philips' siren call.
The best thing about it was to make it backwards compatible, right up to the point that your ten-year old cassette shed oxide over the pristine thin-film head.
Oh, and it had Teletext-style graphics along with a similar refresh speed, which one of my bosses got very excited about. Mind you, he reckoned Philips's CDi was cute, as well ..