How were you tracking each IP address's data usage? Did you parse the logs every request? Store usage in a database? At the application or webserver level?
Webalayzer! I'm not sure there were really any other options at the time other than writing your own. Parsed the apache logs and gave you pretty detailed results and you could see the usage (in kb, which tells you how long ago this was!) broken down by date and IP.
Once you added a redirect rule for the IP to apache you'd just check your log and see the IP that was hitting you every couple of minutes poofed for a good few hours.
Once you added a redirect rule for the IP to apache you'd just check your log and see the IP that was hitting you every couple of minutes poofed for a good few hours.