You can clone with
HTTPS or Subversion.
Add a function that allows you to get a blob's hash just by specifying a branch and a file name (for when you always want the most recent instead of a specific version of a blob).
$.getGithubFileHash(user, repo, file, callback, branch)
Where branch is optional (defaulting to master/HEAD). The callback function will probably just need to have a string parameter that will contain the hash.
Oops! Just now noticed this issue. It seems my pull request is a great middle ground for this for the time being?
more than happy to continue discussion over on #4 if need be!
I'm considering this closed thanks to @brntbeer!