Anonymous's new weapon
Users have no way of knowing beforehand what will happen when they visit the page. Anonymous sympathisers have been diligently disseminating links to the web page via Twitter, frequently using any of a number of link shortening services to obscure the actual URL. In order to maximum the number of hits, Twitter users are in many cases being enticed to visit the page under false pretences.
The attack is part of #OpMegaupload, launched by Anonymous following the arrest in New Zealand of Kim Schmitz, founder of the MegaUpload service which was shut down yesterday in a worldwide operation by the authorities. Last night, the Department of Justice web site was indeed offline for some periods, but things now appear to have quietened down, with the web site currently freely accessible.