An event that affected the world. On December 24, 2005, every computer that was connected to the Internet was infected with a virus that would cause them to crash, and communication networks would simultaneously shut down.
In the United States, the entire stock market was shutdown and information was wiped for an entire hour. After which everything was restored. During the chaos, the US' nuclear defenses were activated and loaded to fire, but the nukes were never launched.
The incident caused the US President Jim Stonecold to take the blame and resign from Presidency on January 2006. It was later discovered that the virus creator was a 10 year old Elementary school student from Los Angeles, California.