Inspired by the Steam Walker by Crabfu Steamworks, Professeur Shadoko of French DIY blog Brico Bidules built this awesome steampunk Steam Ant that's powered by a steam engine, complete with smoke stack!
The engine is a steam boiler that uses a small, dual-acting cylinder. It's heated with Esbit hexamine fuel tablets, which don't produce any smoke or ashes. The legs are made of brass tubes, which are attached to gears, with extruded aluminum feet.
You can see the Steam Ant in action in the video below. It doesn't move fast, but it's incredibly smooth—and pretty stylish, too.
If you prefer something that can move a little faster, check out the A-Pod Robot that moves like a real ant. Want to make your own hexapod? You can build a cheap one out of PVC, or a tiny army of Popsicle-stick Arduino hexapods.