The Great Firewall of Cameron is supposed to block "extremist" websites, and somehow, the website of the respected, excellent Chaos Computer Club, one of Germany's foremost centers for technology research and political analysis, has been blocked.
CCC speculates that perhaps this isn't overblocking — it may be that for the UK political class, the organization that puts on one of the world's preeminent security conferences (the annual Chaos Communications Congress) qualifies as "extremist." I certainly hope this isn't the case, but fear that it might be.
Since July 2013, a government-backed so-called opt out list censors the open internet. These internet filters, authorized by Prime Minister David Cameron, are implemented by UK's major internet service providers (ISPs). Dubbed as the "Great Firewall of Britain", the lists block adult content as well as material related to alcohol, drugs, smoking, and even opinions deemed "extremist". 
Users can opt-out of censorship, or bypass it by technical means, but only a minority of users know how to bypass those filters. Accessing the server directly via http://184.108.40.206/ currently appears to work quite well, thereby rendering the censorship efforts useless.
Internet filters simply do not work, but leaving technical limitation aside, the CCC's example shows that unsolicited overblocking, meaning wrongly classified websites, is a common phenomenon in large censorship infrastructures. However, it may very well be that the CCC is considered "extremist" judged by British standards of freedom of speech.
(via Hacker News)