Stats between 2 commits
git log --numstat --pretty="%H" --author="Your Name" commit1..commit2 | awk 'NF==3 {plus+=$1; minus+=$2} END {printf("+%d, -%d\n", plus, minus)}'
Stats since 6am
git log --numstat --pretty="%H" --since="6am" | awk 'NF==3 {plus+=$1; minus+=$2} END {printf("+%d, -%d\n", plus, minus)}'
Commits per day
git log | grep Date | awk '{print " : "$4" "$3" "$6}' | uniq -c
Commits per name
git log --pretty=format:%an \
| awk '{ ++c[$0]; } END { for(cc in c) printf "%5d %s\n",c[cc],cc; }'\
| sort -r;
Commits per email
git shortlog -sne