The rather cramped streets of Hong Kong are currently lined with tens of thousands of people -- the Umbrella Revolution. The Chinese government, as always, has blocked and censored a number of social media sites so that mainland China can't see what's going on in Hong Kong. The Hong Kong protesters won't be so easily thwarted, however: They are already using a mesh networking app called FireChat, which allows the protesters to communicate freely without any kind of centralized cellular or WiFi network.