http://rescuefox.mozillalabs.com/ is a playable copy. It works in current versions of Firefox. A quick test on MacOS Chrome shows that it appears to appears to work there as well, albeit more slowly and without the background music.
Note that we think we've learned much of what we can from RescueFox and don't intend to drive it forward any further at this point (though that shouldn't stop anyone who feels inclined to fork it). But we'll be prototyping another microgame soon once the Gladius refactoring is a bit further along, and we'll be very interested in having folks help out there...
https://www.pivotaltracker.com/projects/337777 is where a lot of the work happened.
After cloning this repo, run "make submodule" to clone or update the repos that this code depends on (eg CubicVR, Gladuis). Then fire up a web-browser, and surf to the src/ directory to play or test changes that you've made.