A PHP/HTML generated table that displays incoming and outgoing traffic accumulated a) since the beginning of the month and b) since the manual counter was last reset to 0 for any host in a subnet. Data is counted by a set of IP tables rules, picked up with iptables and stored in a mysql database.
There are tons of IP accounting scripts around. Still I made my own, probably because I was too dumb to install one :). Nope, I installed MRTG/SNMP. Rather I thought it would be too hard to find one that fulfills my whishes and needs. And it was good practice. I first made it in perl with my own data files and now switched to PHP/mySQL.
Feel (GPL) free to use it and if there's something you like to be added, etc. you can tell me. I make no promises that I will do it, but maybe somebody else will.
Read the README
See an example output of bipac.
Go to the bipac project page where you can also download bipac.