Hey guys I just stumbled across this exact post on Google. Its actually just been done, the Inkjecta Flite V2 has a Maxon brushless pancake motor in it. You're right, a lot of electronics knowledge went into developing that motor in conjunction with Maxon to run on a typical tattoo power supply. I don't work for Inkjecta but i do help them with R&D. It only takes cartridge needles though (which i prefer), i do have a prototype of a their version to run regular needles at the moment as well.
flite.jpg