Yahoo, eBay, Amazon - $1.2 billion As in the case of the recent Twitter/Facebook shutdown, a Denial of Service shut down 5 of the most popular websites in February 2000 for several hours. Flooding servers with paralyzing amounts of network data, hackers' programs brought Yahoo, eBay and Amazon to a crawl and eventually crashed their systems. Although no financial gain was intended in the attack, market researchers at Yankee Group estimate the crash caused a capitalization loss of $1.2 billion. But for any eBay member bidding on a Jabba figurine at the time of the crash, the loss is beyond price.

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