Milter-greylist

Has anyone already written a script to parse Sendmail's maillog file and 
display some detailed statistics about milter-greylist actions?  I 
thought I'd ask on the list before I try a crack at it.

Statistics like:

* Local users and their rejected message count so I can give them a 
report stating how many messages were blocked by the filter.
* Average delay time for accepted e-mail per user and per sending ip (to 
more easily find domains with badly behaving or multiple outbound mailers)
* Total count of rejected messages per IP to help identify high volume 
spammers.

Thanks,
Mike