A new semi-autonomous four legged robot by the people at Boston Dynamics:

The Legged Squad Support System (LS3) is a rough-terrain robot developed by Boston Dynamics with funding from DARPA and the US Marine Corps. It is designed to carry 400 lbs of payload and travel 20 miles without refueling. LS3 has sensors that let it follow a human leader while avoiding obstacles in the terrain.

[Source: BostonDynamics | Via LS]