No, not one of those white, humanoid Japanese jobs. This is something enttirely different. You honestly have to see this video to believe it...

http://www.youtube.com/watch?v=nUQsRPJ1dYw

Question is, do we cover these with machine guns and lasers and use them as weapons, or do we cover them with cameras and sensors and send them to Mars and other solar system bodies? How cool would it be to have a dozen of these walking around on the summits of the Endeavour hills..?

Wow, that is so cool. I didn't realize how small it was until they showed the hand. Do you think scaling it up to accommodate a robust package of instruments would create additional challenges, or would the same physics apply? I would expect, based on simple geometry, that each time you double its size the mass would increase by about 8x. So there would surely be a trade-off between the strength and nimbleness of those legs.

I also would have liked to see it try and recover from catastrophic flip upside down...

Pretty amazing.

Poolio - check out the other accompanying videos for Big Dog - it's about 100kg and can carry a payload of around 150kg or so which puts it firmly at full size rover scale. The basic locomotion behaviours are impressive enough but the ability to recover from unexpected shocks (like getting kicked off balance) and dealing with truly nasty surfaces (like snow covered rough ground and ice covered asphalt) are amazing. There's a nice summary paper of the development history and general overview available from Boston Dynamics here.

However I think there is one huge problem with this concept - power. The Big Dog uses a 15hp internal combustion engine that probably masses around 15-20kg to handle its maximum 250kg working mass. That's about 11kw of power delivered- compare that to the 110Watts from an MSL style MMRTG (at 45kg) or the 140watts from a Stirling ASRG (35kg or so). Basically this style of locomotion requires two orders of magnitude more power from a source that is half the mass of the best solutions we can use now or in the medium term for space exploration.

It's still awesome technology though.

This one is from Boston Dynamics too:
http://www.youtube.com/watch?v=a0NFrA-Nx4Y

This one is NOT from Boston Dynamics

Big Dog BETA

Big Dog Beta has some, uh, issues...(I just lost it completely in the sandbox!!!)

Amazing technology on all previous versions, though. Eerily smooth & agile motion, very reminiscent of a living creature.