I support error code 451.
According to a story on KQED Radio (San Francisco), the Internet Engineering Task Force is considering creating this code in honor of the late Ray Bradbury. The "451" refers to his classic novel Fahrenheit 451. Appropriately, the code would be displayed for sites blocked due to government censorship.
Internet error code 451 was proposed by Tim Bray of Google. DigitalTrends.com has some great coverage.
Mr. Bradbury denied that Fahrenheit 451 was about government censorship, insisting it was about technological change. Authors often fail to see the thrust of their work. In this case, Mr. Bradbury was simply mistaken. If his novel is not about government censorship, then I have completely failed to understand it.
Wordpress users take note: WordPress maven esmi has created a plugin for your website that will put a ribbon across the upper right corner supporting error code 451. It’s available at http://quirm.net/download/94/. I’ve tested this plugin with half a dozen themes and it’s worked fine. BUT I have to issue the usual disclaimers. This was put together at my suggestion based on the "Stop SOPA" ribbon campaign earlier this year. If it doesn't work with your Wordpress installation, let me know and I'll contact esmi.
A shorter version of this is on my technology blog.