squidGuard is a combined filter, redirector and access controller plugin
for Squid. It can be used to:

* limit the web access for some users to a list of accepted/well known web
  servers and/or URLs only.
* block access to some listed or blacklisted web servers and/or URLs
  for some users.
* block access to URLs matching a list of regular expressions or words
  for some users.
* enforce the use of domainnames/prohibit the use of IP address in URLs.
* redirect blocked URLs to an "intelligent" CGI based info page.
* redirect unregistered user to a registration form.
* redirect popular downloads like Netscape, MSIE etc. to local copies.
* redirect banners to an empty GIF.
* have different access rules based on time of day, day of the week, date etc.
* have different rules for different user groups.
* and much more..

Homepage:
http://www.squidguard.org/
