These scripts will find all git repositories on the local machine, find all commits made by some user (specified as arguments to find-commits), and plot the number of commits, lines added, and lines removed over time. Commits that add or remove over 10000 lines will be ignored (for huge data files and such).
To run:
$ ./find-commits.sh jon@thesquareplanet.com jon@tsp.io > commits.txt
$ cat commits.txt | ./draw-commits.sh