From July 1st and onwards, all PCs sold in China must be shipped with an Internet filtering program called Green Dam. This application, besides being a possible security risk, is supposed to protect the people of China from online pornography, but it could also be used to monitor their online activities and block other, non-pornographic sites.
In protest of this action from the Chinese government, Chinese artist, architect and activist Ai Weiwei has called all Chinese Internet users to stop all online activities on July 1st. "Stop any online activities, including working, reading, chatting, blogging, gaming and mailing. Don’t explain your behavior," he wrote on Twitter.
Ai is perhaps best known as the artistic consultant for design of the the Beijing National Stadium for the 2008 Summer Olympics, also known as the "Bird's Nest," a project he later distanced himself from. He also started an investigation into student casualties in the 2008 Sichuan earthquake, collecting a list of over 5,000 names. He published his findings on his blog, which has been subsequently shut down.