At HP in Colorado Springs, 1981 or 1982, we had some visitors from Palo Alto who showed us a shirt pocket plotter. It looked like a case for eyeglasses which broke open in the middle. The two halves were connected by a telescoping flat bar at the bottom and another bar (for the pen) at the top and clicked into place with enough space between then to engage a piece of 8.5" wide paper. The engineers mentioned a new grit roller system which I had not heard of at the time. This mini plotter connected via HP-IL to an HP41. The plotter drew a space shuttle - a wire frame image many of you have seen.
We were told not to take pictures or even talk about the project until it got to market. I never saw or heard about the mini plotter again but did see the first of the grit-roller plotters come out in a much larger size - the 7470A.
Watching the little plotter was fascinating. When the paper was loaded, it moved in-and-out several times, rather slowly. Then a pencil stylus came out of one half of the pack and went back and forth while the paper moved up and down to create the line image.
I have mentioned this encounter to several people and nobody seems to remember it. Am I in the Twilight Zone? Can anyone confirm what I know I saw?