For general invoicing and hour tracking, I like to post the details of my git commits. Though, I had my own little version of this script, this one posted at stackoverflow was a lot better looking. Posted here for posterity:

function gdaily {
    NEXT=$(date +%F)
    echo "CHANGELOG"
    echo ----------------------
    git log --no-merges --format="%cd" --date=short | sort -u -r | while read DATE ; do
        echo
        echo [$DATE]
        GIT_PAGER=cat git log --no-merges --format=" * %s" --since=$DATE --until=$NEXT
        NEXT=$DATE
    done
}

Which looks like:

[2012-01-07]
 * Refactor list portfolio page css and js.
 * namespace.data include to load fake api data until it is ready. Portfolio list working again.
 * CurrentUser model defaults and code cleanup.

[2012-01-06]
 * Upgrade portfolio call from GET and POST. To be discussed in tomorrow's standup.