I got serious enough about metalwork to start buying machines about three years ago, but became interested in such things helping a friend who bought a used CNC wood router on a bit of a lark. Spent about a month generating gcode in Perl, and then decided to learn how to use Inventor.

And now I have several machines that one generally doesn't find in a second-story urban walkup. (Getting a 400-ish-pound lathe up the steps was how I found my limit there.)