PICS Home Page
www.w3.org/pub/WWW/PICS/

Recreational Software Advisory Committee (RSAC)
www.rsac.org/

SafeSurf
www.safesurf.com/

Ararat
www.ararat.com/ratings/index.htm

Listings of PICS-related filtering software
www.microsys.com/pics/software.htm
www.microsys.com/pics/pr.htm
www.n2h2.com/pics/proxy_servers.html