If you are in charge of administrating a network,
OpenDNS really can help you take charge of your network. Not only are they claiming their service is faster than your ISPs, but they add functionality beyond anything any ISP I am aware of offers. OpenDNS provides the ability to block certain domains, phishing sites, and adult sites. They also offer graphs and reports to help you see your usage. Considering the price, it is worth a look.