Now for a change of pace: PlasmaCAM

All of this talk of water jet cutters and occasionally lasers led me
to this website.

http://www.plasmacam.com/

Apparently you're supposed to buy your own plasma torch, but in any
case, it's a very spartan design of an xy table with a little bit of
z. They claim accuracy of 0.0005 in the xy, making me curious how they
built the actuators and bearings. Getting both ends to move together
on the first axis seems an issue -- maybe a rod with rack and pinion
at both ends would work if you could get rid of the backlash.

Notice that almost all the structural elements are bent sheet metal
and the cable holder saves a bunch of expense from using a flexible
wiring channel.

A small handheld plasma torch is a bit expensive at $1500, but it's
way cheaper than a laser.