In my current project I use URIs to refer to absolutely any entity in a git(-ish) repo. Files, branches, revisions, diffs, anything. URI turns out to be a really good addressing scheme for everything. Surprise. But the most used and abused element is always the path. Query takes a lot of that mess away. Might have been unmanageable otherwise.
In fact, GitHub URIs are a good example of overusing paths: https://github.com/gritzko/beagle/blob/a7e17290a39250092055f...
... all concatenated indiscriminately.