How much does a "motion capture device" cost?
depeds on device!
well it all depends on what type of mocapping you want to do.
The phasespace is like 5-8grand a camera and you need around atleast 15 cameras. Then you need the sensors that go on your arms that are about 100 bucks apiece and you need a min of 6 per limb. and 4 on the waist and 2 on each shoulder. So this set up would at least be 150 grand w/ motion builder
Now the vicon(sp) system is much much more expensive to where the camera's cost around 50grand apiece and you still need atleast 15 of them.
I read somewhere that EA studios mocap setup cost over 150 million don't hold me to that, that may of just been down the rumor mill.