Ask HN: How have you used 3D printing?

I've never used the Shapeways service, but I had some prototypes 3D printed before. It was a few years ago, and it was just some parts I used to make a mold for metal casting.

One of the most interesting things I've seen made by Shapeways has been the jewelry that some people have made. Examples like http://www.shapeways.com/model/107269/structural_skull_ring.... and http://www.shapeways.com/forum/index.php?t=msg&th=1664&#...

I've used it to build parts for a RepRap printer, interestingly enough: http://www.heatsynclabs.org/wiki/Phoenix_RepRap

I want a light switch/button for my home theater, and I intend to 3d print that. I am also working on a front door bell panel (with camera, LCD, etc) that will probably be printed.

The guy I know with a printer has used it primarily for making toys and gifts, but he also needs the occasional custom camera mount, e.g. for sticking 2 tiny cameras on a model plane.