Remember Boston Dynamics, the company responsible for the oh-so-creepy BigDog robot? Well they're still at it, except now they're working on a cheetah-like robot (called Cheetah) that can chase us down like prey, and a humanoid, bipedal robot that looks like the Terminator crossed with the Headless Horseman.
According to Wired's Danger Room blog, Cheetah will run "faster than the fastest human", thanks to a flexible spine, articulated head and (possible) tail. It will also be agile enough to zig-zag and "stop on a dime." Boston dynamics sees Cheetah being used by militaries in field situations, as well as in emergency response scenarios.
As for Atlas, the acephalous wonder is an evolution of Boston Dynamics' previous Petman robot. When complete, it will have the ability to walk using a heel-toe stride at 3.2 MPH. It will also be able to crawl and manoeuvre sideways to slip through tight spaces. [Danger Room]