I have been collecting Music and Movies for most of my life. It is a collection of the formats as much as or maybe more than it is for the entertainment value. I like what I call obsolete technology. It is my goal to have every format that audio and video have ever been recorded onto.
In my Audio Format Collection this is what I have:
16 2/3 RPM in 7"
33 1/3 RPM in 10",12" (Albums & Singles) [Mono, Stereo & Quadraphonic] and 16"
45 RPM in 4"{Flexi-disc}, 7" and 12"
78 RPM in 5", 6",7",8",10" and 12"
4 Track Reel To Reel in 3 3/4ips and 7 1/2ips
3M Cantata Background Music Cartridge
Sound Tape Stereo Cartridge
Playtape
4 Track Cartridge
4/8 Track Cartridge
8 Track Cartridge [Stereo & Quadraphonic]
Cassette (Albums & Singles)
Digital Compact Cassette
Compact Disc (Albums & Singles)
Mini Disc
Downloads <Which doesn't really count, since it is not tangible>
My Video Format collection is just as diverse:
Beta Tape
VHS Tape
D-VHS Tape {D-Theater}
Video 8 Tape
CED {Videodisc}
Laserdisc
MovieCD
VCD
DVD
Digital Video Express DVD {Divx}
Superbit DVD
HD-DVD
Blu-ray
Downloads <again, don't really count>
I am far from done, however. There are still many formats to go before I have them all. But the fun is in the search.