You might remember the LEGO "3D Printer" by arthursacek some time ago, this time he goes one step further and make a 360 degrees miling machine.
"There is a lot of improvements, but the most important is that it is running leJOS with a linked PC. Now there is no more file size restrictions. All the data is in the computer that sends small amount of coordinates to the NXT every loop."
It was developed to participate in the WRO 2011 - Abu Dhabi in the "LEGO Robotics Experts" area, among many other fantastic creations, as you can see in this video: