A few weeks ago at a craft fair, I spoke with Kelli Nemec of LaserMade. Kelli works in acrylic, using a laser to cut intricate designs in plastic. You can see one of her designs off to the side there - a "No-L" ornament designed to celebrate the holidays with a little wordplay. If you can't tell from the smaller image, you can click through - the black and red are totally separate pieces of acrylic, perfectly cut to align.
Laser cutting and engraving is not yet a widespread art. I can't imagine the startup costs to build your own laser is cheap. Most people who make use of it create the design and then send it off to be processed somewhere - like LaserMade. The appeal is twofold: reasonably complex designs can be reproduced without the molding process required for metal or resin, and actual production is fairly inexpensive. The acrylic and wood generally used for the process are cheap material, and it doesn't take much work on the part of the person doing the cutting, assuming the design was well-done.
If you have design you would like to see produced inexpensively, acrylic laser might be the way to go. It is particularly suited to angular or precise designs. Another of the pieces Kelli had for sale was an ASU Sundevil-themed ornament incorporating the sun and pitchfork shapes favored by ASU. Using the laser, she was able to create a sharp, iconic look in plastic. It's also perfect when you want a design in colors that just aren't easy to achieve in metal.