The Uncensor campaign recently launched an
online protest [site no longer available] to take place on 30 July.
The action page contains instructions on how to add a small bit of code to your blog theme to participate in the protest – which will activate automatically on 30 July.
The page explains in more detail and includes a way of previewing what your blog will look like on the day (the screenshot above shows the banner on the Amnesty website).
Disclosure: I’m working on the Uncensor project, but this action is not my work. My bit will be launched real soon now :)