“Scarcely a week goes by when I don’t hear about yet another new
(or relatively new) open source project that stands in for a
proprietary solution. Consider Untangle, a network gateway
appliance than runs on any commodity hardware and handles spam,
firewalling, Web filtering and protocol controls, VPN, and tons
more. They’ll even send you a preloaded demo server.“Untangle bundles 12 GNU GPLv2-licensed apps under one roof,
including reporting and analysis tools to help you make sense of it
all. The OS also is included–all you need do is download an ISO
and burn an install disc, or boot the ISO in a virtual
machine…”