The internet is not going to take the possible passing of SOPA and PIPA lying down. As a protest, today is the day of the SOPA Blackout, in which many of the sites and services we use every day take a stand--and go black, just as they might be legally forced to do if these bills pass. You know about Wikipedia, sure. But there are lots of other protests going on around the web today (and, apparently, in real life), and some of them are really interesting and creative.
If you're interested in having your voice heard, Ars Technica has a great piece laying out the best ways to protest.