Clean Web filter is pretty decent. It's marketed by the Clean Web company: www.cleanweb.net/ Actually it's a proxy server. You put the filter lock on your computer, and all your http requests go to their server through port 8888. They have a team of people who review web sites based on different criteria (porn, criminal activity, etc.) So it's not just a "dumb" filter that automatically bars sites based on some word usage screen. Real humans make decisions on what is barred.
For the wages of sin is death, but the free gift of God is eternal life in Christ Jesus our Lord.
(Romans 6:23, WEB)