A couple of useful git commands for styding big git repositories:

Rank contributors by contributed lines of code in HEAD

git grep --cached -zIle '' |\
     xargs -0n1 git blame -e |\
    sed  -n 's/^.*(<\([a-zA-Z.]*\)@.*/\1/p' |\
    sort|uniq -c|sort -rn >authors-by-line.txt

sort branches by last modified date in the remote repository

git for-each-ref --sort=-committerdate \
    --format='%(committerdate:short)%(authorname)%(refname:short)' refs/remotes >branches-by-date.txt