Analysing SVN Checkins

Are there any tools out there that can be used to analyse SVN check-ins? I thinking it would be interesting to run a series to checks to be able to understand metrics such as how many characters of code per day does each developer on a project commit; what percentage of committed content is comment, versus code; what percentage of each developer’s code has been replaced or modified by others. There could be all kinds of ways to skin the cat, but is there something that does it already?