If you thought that private, LEGO surveillance blimps were something from some kind of bizarre steampunk dystopia, you'd only be half-right. Two endeavouring LEGO tinkerers, Tyler Westmoreland and Chris Shepard, have brought such a thing into being using nothing but Mindstorms and a couple of balloons.
It's not the most menacing drone there ever was, but it's pretty cool for a DIY job. All the code for the blimp and its controller are open source too, so there's nothing stopping you or anyone else from preparing an army of the things. Strap a 1.8 gigapixel military drone camera on there and you're really in action. That last step might be a little hard though. [Dexter Industries via Engadget]