The Dutch artist Theo Jansen creates huge mechanisms from PVC tubes and lets them roam freely on the beaches. He calls them Strandbeests and they really are a sight to behold.
Some of them have stomachs to store wind so they can walk even when there's no wind and some can even tell when they are walking into the water. I would love to see one in real life. Until then, I'm the proud owner of a mini-Strandbeest. You can buy those kits off Ebay or from Jansen's own site I linked above and even for someone with as little patience as myself, they are easy to assemble.
Just don't be intimidated by the number of parts. It's basically just six steps, repeated a lot of times.
Part of the legs:
The two main parts of the beest:
The finished beest:
It walks really well. You can just blow on the wind wheel, you can crank shaft by hand, you can of course put it outside or you can use a hair dryer, like I did here:
It even manages small obstacles. The tray slides a bit on the floor or the beest would have just walked over it without the slightest problem, but even so it walks on and off.
The construction is really simple, but ingenious. I'm probably going to get myself the second kit Jansen sells as well and I wish he'd sell his others beasts in miniature form as well.