I've got an SX-70 on the shelf. Damaged, alas; the switch/sensor which informed it of the end of an ejection cycle is stuck, and if you can still find a cartridge it'll immediately eject the entire contents thereof. Repairable but not really worth repairing... but I sorta like it as a technocultural artifact, sharing a shelf with a Kodak #2.
The SX-70 really was a lovely job of "what can we do if we discard all the assumptions". Nonspherical optics, a disposable flat battery in the film pack (those batteries were actually overkill for this application), the film, and even the flashbar with its automatic sequencing from bulb to bulb were all remarkably elegant solutions.
Unfortunately it wasn't an especially good camera -- awkward to hold and use -- but the engineering deserves applause.