[mothered]

With regard to Internet attacks and cost of damage due to downtime or otherwise, I clearly remember Mafia Boy back In 2000.

at 15 years old, he executed a massive denial-of-service (DoS) attack that crippled some of the internet’s most popular websites. Calling the attack Rivolta, meaning “riot” in Italian, he brought down Yahoo!, eBay, CNN, Amazon, and other sites, causing an estimated $1.7 billion in damages.

It was, for Its time, a very significant and costly attack.