Mechanical Engineers from Carnegie Mellon University built a robot that can sprint across water. The robot was built to emulate the motions of the basilisk lizard, an iguana that lives in the rain forests of Central and South America.

The inventors imagine a day when a more developed version of the robot could be equipped with biochemical sensors that monitor water quality; be deployed with cameras for spying, search-and-rescue or exploration; or be outfitted with bacteria to break down pollutants.

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Tom Rose built an under-water rebreather from inexpensive parts from Home Depot. A rebreather scrubs carbon-dioxide out of air, allowing it's user to re-use the air they breathe out. A rebreather is much lighter than the equivalent weight for a standard scuba setup, and the diver is less detectable, since their exhaled air isn't sent into the water as bubbles.

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A paperclip will float on water due to surface tension. This picture is photographed through a grill, and the deformation of the water can be seen.

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