You can clone with
HTTPS or Subversion.
Could you put PIE.js 1.0.0 in a "build" folder on github? (And update it with each new version)
That would make it linkable from any web page and more fresh than this CDN, still in 1.0 beta 5:
Thanks for the suggestion, but I'm going to decline -- GitHub is not suitable as a CDN so I don't want to encourage people to use it as such. I will try to get it updated on cdnjs, and I am also working to get access to a proper CDN that I can control going forward (this will become very important for 2.0.)
Opened pull request for cdnjs -- track cdnjs/cdnjs#286 to see when it gets accepted.