Well, O2 has parental controls and automatic internet filters for everyone else as well, and there is a site to see what it blocks. I found that sites such as Agilent, CNN, and the EEVBlog forum itself were all blocked under the parental controls for K-12 students. The only thing i found unblocked was the useless game Club penguin. If I were a parent, I would rather my kid be looking at oscilloscopes.