Joris Laarman is an artist that has utilized his MX3D-Metal robotic arm 3D printer to print in metal mid-air. He has used this technology to develop some really cool chairs and benches:

However, now he is releasing the designs to the Makerchair, a chair which is printed in jigsaw puzzle pieces in 77 - 202 different pieces. It can be printed at home on an FDM 3D printer and then assembled.