If you are looking for a free, effective, internet filter that can do both blacklists (banned site lists) and content filtering (looking for text in packets) I think I’ve found one that works well. You can even whitelist/blacklist your own. For example I whitelist slashdot.org (sometimes the comment pages are raw, but I don’t care). I blacklist images.google.com. Free blacklist updates, free for home use. Unlike ContentProtect (what I was using) it doesn’t hog any machine resources. Works “behind the scenes” quite well.
http://www.cogilab.com/us/homeedition/index.htm
I’ll try to put an install HOW-TO up soon.
A few things I don’t like about it are:
1) It kills the browser process after a violation. There are reasons to do this, you can change this behavior.
2) No override. You can go whitelist a site but there is no way to put in an override password when a violation is found
3) No ability to email the logs, etc. I think you can administer remotely though.
4) I think I had to login as admin and change the unlimited profile to include content filtering (blacklists was default)