Silent Runner is Arduino powered hobby blimp with key structural elements printed on 3d printer. If you want to build it yourself everything is open-sourced and can be found on link bellow the videos.
http://www.silent-runner.net/index.php/Main_Page
http://www.thingiverse.com/thing:31180
http://www.silent-runner.net/index.php/Main_Page
http://www.thingiverse.com/thing:31180