Here's a Kickstarter project that I just contributed to. The founders of SketchChair have developed software that allows you to easily design or customize a chair that can be cut by CNC routers (such as ShopBot), Laser, and other computer-controlled tools. The software will be free but they're looking for funding for development of their online community for sharing chair designs.
Entries in cool (3)
I don't know how long this link will stay active but here you go. This is an amazing do-nothing machine that you need to see to believe.
Thingiverse user sideburn posted "Invaders!" recently and they're way cool. If you have or have access to a 3D printer such as the MakerBot, RepRap, Dimension, Z-Corp, etc. then you can print out your very own Space Invaders ships*!
Thingiverse is a community site that encourages the free sharing of designs that can be made at home with (mostly) sophisticated tools or even small-batch manufactured depending on the license. It's open-source for tangible stuff.
*not actual size