Printer: an open source kit for exploring internet-of-things printing
gofreerange.com
gofreerange.com
Send a message or a picture using the demo apps
There's also some fairly comprehensive documentation on the github wiki, including an architectural overview, and building your own printer: http://github.com/freerange/printer/wiki
https://www.adafruit.com/products/600 http://www.sparkfun.com/products/10438 http://proto-pic.co.uk/thermal-printer/
See https://github.com/freerange/printer/wiki/Making-your-own-pr... for more information...
If you look at the Arduino code (https://github.com/freerange/printer/blob/master/printer.ino), all it does is download a stream of bytes, doing some very rudimentary validation (Content-length), and then sending the bytes out on a serial port.