Blimpduino is a very low cost open source autonomous blimp. It consists of an Arduino-based blimp controller board with on-board infrared and ultrasonic sensors and an interface for an optional RC mode, a simple gondola with two vectoring (tilting) differential thrusters, and ground-based infrared beacon.

It is available as a commercial kit ($89) from the Maker Shed

This is the repository for the board's code, which can be found in the download section at right. It requires the free Arduino IDE to edit and upload the code to the Blimpduino board.

More information and instructions at DIY Drones