Wikipedia is killing me =) They blocked the English version for 24 hours. No matter the motives (ok, SOPA is realy not great thing), but how it's done! Initially full article is loaded, and when the page is fully loaded, it is removed and there is black div in full screen, and an inscription, such as blah blah, we are disabled. That is, you can use Wikipedia: stop loading the page at the time when the article is fully loaded, and the banner is still not =))
UPD. As they told, this is because of search engines like google. To not allow wikipedia's articles to be down shifted due blackout in one day.