The Wikipedia has blacked out the English version of Wikipedia for 24 hours on January 18, 2012. Wikipedia says that this has been done to raise awareness about the U.S. Congress' anti-piracy bills, SOPA and PIPA. Wikipedia mentions "SOPA and PIPA are real threats to the free and open Internet. This legislation, if passed, will harm the free and open Internet."
"For over a decade, we have spent millions of hours building the largest encyclopedia in human history. Right now, the U.S. Congress is considering legislation that could fatally damage the free and open Internet. For 24 hours, to raise awareness, we are blacking out Wikipedia," the message shown to viewers on Wikipedia page.
How to Read any Wikipedia Article on Blackout Day?
On request of the Wikipedia community, the foundation has decided to make available English Wikipedia during an emergency. So, the simple way to access any Wikipedia article is to read in mobile devices. Wikipedia is also accessible on smart phones even on the blackout day. The mobile version of the site can also be accessed on desktop browsers through m.wikipedia.org without any problem.
The desktop version of the site can also be accessed with very little work. Actually, the protest message shown today on Wikipedia articles page is powered by Java Script (a browser end script). So it possible to view Wikipedia by completely disabling Java Script in your browser.