Q:

Count git commits by a user globally

As a crude measure of productivity, I would like to measure the number of git commits I make during a given time period. Ideally I would like to also measure something like "amount of text" changed, but I can see how this might be harder. Many of my projects are home projects, so I would prefer to get that information from git. 
I know I can do git log --author=johnsalvatier to get the all the commits I've done for a given project, but if possible I'd like to do this globally. Is that possible?

A:

You can always script it, but git by itself doesn't know about any repositories on your local system beyond whichever one you're currently in, and it certainly can't find your repositories on other computers without help. :-)
However, if all of your projects are open source, you could check out http://www.ohloh.net/.

