The Hex Bug, at $10, proves to be a perfect platform for building your own droid. Out of the box, it has pretty limited functionality. It walks forward until its antennae bump something, then it backs up and turns left. Applied inspirations shows us how you can replace the bug’s brains with a microcontroller to give it much more life. Instead of hacking into the existing electronics, they chose to completely replace the board. The final result, though still only able to turn one direction, is much more robust.  They discuss the ability to add numerous sensors as well as pre program different behaviours and personalities.