A friend forwarded this to me. Cool application of Lego to make a printer. The video author's comment on YouTube:
"Lego felt tip 110" printer connected to an Apple Mac. This is not a kit you can buy and does not use MindStorms. I designed/built/coded it all from scratch including analog motor electronics, sensors and printer driver, the USB interface uses a "wiring" board.
Once again, this is not my work. I'm just posting something I found cool.
https://www.youtube.com/watch?v=zX09WnGU6ZY