OpenDNS is a free DNS provider who does the Web-content filtering on their end. You don’t need to install any software to filter any content. All you need to do is register and follow the setup instructions, once that is done you will have access to your own area where you can filter phishing sites, give you the power to filter out adult sites and proxies among more than 40 categories, and provide the precision to block individual domains.
All you have to do is, set the DNS server to 208.67.222.222 & 208.67.220.220 and do the content filtering on your very own control panel!
Also this is a great advantage to parents and you will save a lot of money on buying content filtering software like Net Nanny etc…
Everything you need to know can be found on here, and I highly recommend anyone to use this Free service.