Speaking of cool: a short article on a robotic water strider:

Water striders are insects that can perform amazing feats of dexterity on water. They perch on the surfaces of ponds and slow streams as if on solid ground. And, as their name suggests, they can skim blithely across the water's surface, just like surfers on a wave.

Not to be outdone by these humble creatures, John Bush and his colleagues at the Massachusetts Institute of Technology have [created] a mechanical device that can do the same.