SOPA protests shut down Web sites

This is what happens when you make the Internet mad.

On Wednesday, a group of technology companies began an unusual form of protest: The firms shut down or replaced the content on their own popular Web sites with protest messages to show their unhappiness with two Internet-regulation bills grinding through Congress. Around the country, Americans woke up without some of the oddball essentials of online life. No Wikipedia. No Reddit, a compendium of links to stories and funny pictures that draws millions a day. And no I Can Has Cheezburger?, the world’s best-known collection of funny cat pictures.