CNC milling has been around for a while, typically with shop-based machines; we haven't seen a portable one since ShopBot discontinued their Handibot model. But Utah inventor Henry Ashworth built a portable CNC unit that takes a common Makita router, can be set up outdoors, and can engrave in concrete and stone. The engraving can then be filled with resin or painted. Ashworth launched a business around the machine called Red Art Technologies. He now sells the CNC Pro, as he named it, along with specialty engraving bits. The applications are numerous: Being portable, the machine can easily be moved and indexed, and has an infinite cutting area. It can even do walls. It breaks down to fit in this robust portable case. See the CNC Pro in action below.