An interesting
Instructable about quadcopters. It doesn't actually have a lot of details about building one, but has some good low-level technical stuff.
An
overview of the math of controlling brushless motors and gimbals.
Sainsmart sells nice looking Arduino clones and other interesting electronics. PLA too!
jj604 has a
neat 1S/2S brick made from a LemonRX receiver and 1.7g servos.
Multicopter contest over at
reddit.
