KalNet Message Board

Homebrew circuit boards where you laser print them, iron them onto the board, etch, and then solder yourself:

http://fullnet.com/~tomg/gooteepc.htm#1

Shapeoko is a desktop CNC:

http://www.shapeoko.com/

Build your own radar

http://hackaday.com/2015/04/07/build-a- ... ugh-walls/