QuickType 1520 is a super simple, but cool program for the Commodore VIC-1520 plotter.  Basically you can use the plotter like a typewriter with this handy utility.  I found this on shareware disk 4029 (Business #3) from "COMPUTER NUT" in Lancaster, CA.  There are several other shareware programs on the disk that someone might find interesting, so I included a screenshot of the disk directory.