GPS vs. Gaileo vs. Inertial?
 

I was just reading about Gaileo on another forum. Is it possible that satellite positioning systems might be largely replaced by inertial reference systems? (yes I'm not sure of the difference between reference and navigational, but I think they work the same)

The only experience I've had is throwing my Wii controller around, but I've been told the new chip based ones are getting very accurate.

Indeed, one I read online about one type operates by measuring the mass temperature increase relative to a control gas and thus figures what the accelaration was! If that works how I think it does that's astonishing.
(moving matter radiates energy - chemistry 101)

?