I am always quite fond of statistics.
Sometimes there is a feeling that the pace of the project is slowing down, but in fact bigger changes take more time and therefore ‘look’ sluggish. But with some real analysis tool you can verify or invalidate this. Never underestimate the truth rock-hard data provides.
The downside is: is someone tweaks his output, because he is aware of the measurement, the stats can be distorted.
gitinspector is a Python-script which creates some output about the authors, their activity, .. as command-line-message or even HTML.
Easy to use (download, extract, run) and versatile.
I can’t provide any useful example-output, because for most of my repositories I am the sole author.