UK police reportedly foiled an attempt to launch a DDOS attack on websites relating to the royal wedding earlier this year. The planned attack was apparently cooked up by a 16-year-old, and could have prevented millions from watching the wedding online.
Not that some of the royal wedding websites needed any help to crash under the massive load to which they were subjected during the wedding on April 29th. At times, some of the sites were being accessed (legitimately up to 2,000 times a second), and some ran slow or crashed even without a DDOS attack.
DDOS attacks are one of the most common, but also most effective, methods of disrupting a website. They work by flooding servers with data requests from multiple machines, often using specific software such as the notorious Low Orbit Ion Cannon (LOIC) developed by members of Anonymous and LulzSec.