Simple web form for static assignment of DHCP leases
...Network devices (usually PCs) are separated into subnets by department and use triplets (hostname, MAC address, IP address) for identification. Information is stored in MySQL and only exported by your explicit desire. Subnets are rarely changed, so there is no web interface for them - you have to edit the SQLtable SUBNET manually.
PHP/HTML IP accounting table displaying in/outgoing traffic accumulated a) this month and b) since the manual counter was last reset for any host in a subnet. Data is counted by a set of IP tables rules and stored in a mysql database.