NEW YORK (CNNMoney.com) -- The website-attacking group "Anonymous" tried and failed to take down Amazon.com on Thursday. The group's vengeance horde quickly found out something techies have known for years: Amazon, which has built one of the world's most invincible websites, is almost impossible to crash.

...a DDoS attack, short for distributed denial-of-service -- and it's hard for most websites to defend against. The attack itself isn't sophisticated. It's the equivalent of simply hitting the "refresh" button on a website thousands of times, which attackers use automated programs to do.

Why attackers can't take down Amazon.com -- CNN

Great example of the power of EC2 and an automated scaling architecture.