Favorite obsolete formats.....

What are your favorite of these? I’m unsure if any stations broadcast in AM stereo nowadays. 8 track, Mini-disk, Cassette, VHS, CED, Beta, DAT, Reel to Reel, Am Stereo, Laserdisc, Quadraphonic, Dolby FM. Surely many formats have been overlooked.
Strange to see SACD get mentioned.  The format is still growing and should be releasing its 15,000th release later this year.
Cassettes were an amazing convenience for listening in the car or the Walkman.   It’s slow tape speed and small size was never intended for audio fidelity.  It did lead to a cool performer name Dolby and left us with ever evolving dolby apps added to audio visual receivers that are hardly used 
The Golden Record aboard Voyager. Probabilistically, a complete waste of time and effort.