The maintainers of the contraptor project have done some pretty neat demonstrations with an Arduino. I was particularly impressed with this X-Y plotter/drilling

The maintainers of the contraptor project have done some pretty neat demonstrations with an Arduino. I was particularly impressed with this X-Y plotter/drilling assembly: http://www.contraptor.org/fast-drilling-contraption http://www.contraptor.org/fast-drilling-contraption