4pcb is a miniature quadrotor built on a single printed circuit board. (The board is its structure and its electronics.) It weighs 125 grams and is powered by four brushless motors. The processor is an Arduino Mini. It's radio controlled and has a 6-degree-of-freedom inertial sensor for stabilization. The control loop still needs some tuning, and yes it could also use some landing gear. More info: http://scolton.blogspot.com/search/label/4pcb