Didn't have a specific example in mind; there is definitely opportunity for Github to help with education and adoption.

For some reference material check out:

  http://book.git-scm.com/5_git_hooks.html
  http://progit.org/book/ch7-3.html

And a couple simple examples:

  http://mark-story.com/posts/view/using-git-commit-hooks-to-prevent-stupid-mistakes
  https://github.com/ReekenX/git-php-syntax-checker