Felix Vorreiter invented the txtBomber, a handheld gadget that prints text on any flat surface using Arduino-controlled pens:

The txtBOMBER is a one-hand-guerillia-tool - a machine not much bigger than a pressing iron - that generates political statements on the fly and immidiately prints them on any flat surface.
If you feel you are part of our modern viewless generation, the txtBOMBER is the perfect tool for you!

Link via DudeCraft | Video