content filtering on linux/smoothwall

im planning on installing smoothwall on an old box and making it a hardware firewall between my wireless router and my modem, no problems there.

but i recently decided that id like to play around with content filtering (web sites) and what not. i guess im looking for a linux app and it's gotta be free. any suggestions?

i just want something that would basically intercept www requests and if they are bad (whats bad can be set by administrator) it redirects to a not-found or a no-no page :)

incoming content monitoring is secondary but that would be really cool. i would think it would be a lil harder though, so not a must and remember i have maybe 400 mhz and 128 mb ram tops, 5-10gb hard drive space. if required i could think about putting up another box and set smoothwall to forward to it? anyway, input would be great.

I believe "Dan's Guardian" will run on a Smoothwall.

If your going to be messing about with smoothwall, then also look at ipcop.
If I recall correctly... ipcop was a fork of smoothwall when smoothwall decided to have both corporate and express. the express verison is the home user version which excludes many features. ipcop has more features than smoothwall express and has a larger community developing addons for it.

http://www.ipcop.org/
http://www.ipcop.org/modules.php?op=...me=IPCopAddons

You may want to checkout IPCop. It does everything you are looking for and much more. I've been very pleased with it.