Geoffrey A. Fowler, The Wall Street Journal, Jan. 18, 2012
From the article: "Wikipedia and other popular websites converted their homepages into virtual protest banners early Wednesday as part of an effort to stop Internet piracy legislation that is being considered by the U.S. Congress. The protest was joined, too, by search giant Google Inc., which didn't shut down its site, but around midnight covered most of the logo on its U.S. homepage with a black box, and added a link asking users to tell Congress "please don't censor the web." Craigslist Inc., the popular classifieds site, also put up a black homepage that offered information about the laws and scolded "corporate paymasters" to "keep those clammy hands off the Internet!" Read more
See Also
Wikipedia Blackout Lets In Some Light
Sarah Maslin, The New York Times, Jan. 18, 2012
What is SOPA?
Mike Zaplar and Kim Hart, Politico, Jan. 12, 2012