Current obsession: vintage Autopen signing machines. Used for mass-producing signatures with real pens, the machine was invented in the 1950s and is decidedly non-computerized: the plastic templates used to drive the pen look like the one below.
These templates can still be ordered online for $200, and I am completely fighting the urge to buy one. The company is still in business and makes CNC versions that take an SD card instead of a physical template. Below is a room full of machines, signing junk mail letters.
This amazing book includes printed mylar signatures by JFK’s fleet of Autopen robots as an aid to identifying real and generated signatures. A deeper forensic analysis is available from this 1973 article in the Journal of Forensic Science.