The English version of Wikipedia is offline, and Google has put a blackout spot over their logo. In both cases, the goal is to get readers to contact their members of Congress and tell them no on SOPA and PIPA. Fortunately, my member of the House, Raul Labrador, has indicated opposition already. It still would not hurt to contact your member.
UPDATE: Just to be sure, I emailed Rep. Labrador and Sen. Crapo about SOPA/PIPA. I would have contacted Sen. Risch as well, but his server seems to be crashed. (I wonder why?)