GateWall 

GateWall is an easy to use toolkit to provide Internet access for LAN users. The network administrator will be able to supervise Internet connections, calculate consumed traffic, email detailed usage reports to consumers and much more!
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ComTun 

A powerful and easy to use Proxy/Firewall for internet connection sharing. ComTun has many advanced features useful for both business and home use. With support for access control and banner blocking, you have ultimate control of your connection.
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