As I mentioned, it is only available for certain models of Canon DSLRs (with specific firmware - usually the latest version). The list of supported camera is: 5D2, 5D3, 6D, 7D, 50D, 60D, 500D/T1i, 550D/T2i, 600D/T3i, 650D/T4i, 700D/T5i, 1100D/T3, EOS M and "in progress" the 70D.
Several people asked whether there were equivqlents for other makes of cameras. A quick search suggests that "Nikon Hacker" is trying to do something similar for Nikon cameras, but I know nothing further about this.
Here is the result of stacking the images of the Uruk-hai model I took in the demo.