ISA Stats allows to control Internet usage in your company.
Statistics collecting system analyses traffic and summarizes the information about working process. It gives a chance to find out the most active users, to reveal when and which Web sites they have seen. If necessary, its possible to gather the information about the most popular and actively used sites.
The control over users is made both in real time and on the base of collected data.
Statistics gathering, suitable report system, monitoring of used Web sites in real time, blocking unwished sites, and remote administration.
It's open source!