My son is 7 now, hitting a bunch of flash & Java games at various sites on the web. I've always made a habit of keeping an eye on what he's checking out, and the other day on the sidebar of one of the game sites was an ad for "Date Hot Local Girls!" So I knew... it was time.
Not wanting to fork over the wad of cash for CyberNanny or whatever else is available commercially, I decided to give dansguardian a try. Fortunately, FreeBSD includes it in its ports tree, so installation was pretty easy. dansguardian works in conjunction with a proxy server, so I had to install Squid first.
There ended up being very little configuration that was necessary. The only quirk that I assume is unique to FreeBSD is that it doesn't extract and place the phraselists in the appropriate directory - but that's easily remedied manually.
Nice little package - a few tweaks to tighten down the controls even further (the default configs are set for a pre-teen level) and tonight my son asks me why he can't get to the site with his fishing game (the one that had the hot girls ad). Oh, that's just the computer protecting you, son.
On edit: Forgot the link!
http://dansguardian.org/