This may be the ugliest bash one-liner ever:
git log --pretty=%h | tail -r | while read sha ; do if [[ -z $(git rev-parse --verify $sha^2 2> /dev/null) ]] ; then echo '----' ; git show --summary $sha | tail -n+5 | egrep -v '^ (?:create|delete) mode' ; git --no-pager diff --color -U999 $sha~ $sha | awk '/diff --git/ { sub("^a/", "", $3) ; print "===" $3 } /diff --git/, /@@/ { next } { print }' ; fi ; done | ansifilter -H | sed 's/^----$/<hr \>>/;s/===\(.*\)/<h2>\1<\/h2>/' > history.html
It runs through the git history of a project, printing the full message for each commit, followed by a complete listing of each changed file, with added, removed or changed lines highlighted. It then outputs the result into a big ugly HTML file. Like this.