What about Bess, the Internet Retriever?
My high school here in Seattle uses N2H2's Bess for filtering. It seems to be fairly common, and it's very limiting. My teachers have even complained, noting that sites like "excite.com" are banned due to the word "excite" being contained in the URL. Their excuse for that specific block is that, somehow on their planet, the word "excite" relates to the idea of "sexual excitement," which, again somehow on their planet, is offensive to 14-18 year old students, all of which have experienced sexual excitement on their own and are able to handle.
I don't know much about filtering software. While the software disturbs me, especially in the bigger picture (laws requiring it, etc), it's not enough of a hinderance to me personally to prompt further investigation. When I'm investigating marijuana for a school project (I actually was assigned that project last year) and I am blocked from non-government marijuana sites, I just make a snotty comment and finish my research at home.
But the point is that it seems Bess is undermentioned. Is it not as big of an issue as the other filtering software companies, or what? Maybe I am misunderstanding exactly what filtering software is. Does Bess' purpose differ from CyberPatrol in some way that I'm not aware of?