I draw comics, and for part of my workflow, I print software-modified "pencils" in light blue onto the paper, then draw the final inks over that. The blue layer doesn't show up in scans or photocopies. This process works pretty well for me, but details of the lineart often get blurred together, and the printer often refuses to print because the three unused color cartridges have dried up. The printer I normally use just broke, so I'm hoping to replace it with something better for this use.
Ideally I would use monochrome printing with cyan ink, but I haven't found any off-the-shelf options. I was thinking of just buying a black-only inkjet printer, using up the black ink and refilling the cartridge with cyan, but I don't know how well that would work. If the black ink never gets fully washed out, the printed lines would show up in scans of the final product.
If anyone has experience with this or similar problems, I'd appreciate hearing about it.