Nicholas C. Lewis is developing an interesting Kickstarter project known as the InkShield.
This shield allows you to connect a HP C6602 inkjet cartridge to your Arduino turning it into a 96dpi print platform. It only uses 5 pins which can be jumper selected to avoid other shields. It is designed with a Arduino Mega footprint but fully supports both the Arduino and the Arduino Mega. It is designed with all through-hole components to make assembly easy even for beginners.
The project is mostly funded and it looks like Nicholas has done a lot of work on this design, including an on-board 18.5V boost converter for the Inkjet head. He states that all hardware and software code will be released when the initial production run is completed.
It would be nice to add a couple of mice sensors to print pixels ad the right rate when moving on paper..
I’d love to see someone use pigment-based ink coupled with an X-Y positioning system to directly print the etch resist for DIY PCBs