Thanks Matt. The majority of my work is done with a GRS Gravermax. It's an air assisted system that uses the same gravers as hammer and chisel. Think of it like a miniature jack hammer. A tiny piston provides the impact force rather than a hammer which allows one hand to control the graver and the other to turn the work into it. When I started engraving I only used the hammer & chisel, which I still enjoy, but I have much more with the air tool.
You can go to www.grstools.com to see the machine and get a better description.