"Untangle could turn out to be a poster child for free software.
The company started out considering both free and proprietary
software for its platform, but settled on a flat-out, pure-play
open source approach. In return, they demonstrate the kinds of
enhancements a commercial firm can make to free software in a range
of areas commonly known as productizing.
"Untangle is an integrated computer security solution aimed at
small businesses (about 250 employees or fewer). Today they unveil
their Untangle Gateway Platform, billed as 'the world's first
commercial-grade open source solution for blocking spam, spyware,
viruses, adware and unwanted content on the network...'"