The Xerox 3700 is a high speed laser printer of the first generation. It has
a built in terminal/controller. The 5 1/4" 360K floppy was used to load fonts
and emulation software. Most of them were based on the Dataproducts printer
interface. It was built on the chassis of a Xerox copier of the times.
Usually they have a nice 5-7mw laser tube and power supply in them. I don't
know of any other current use for them.
Paxton