Blue Security Gives Up, Spammer Wins

Blue Security is a Anti-Spam company which aimed to to stop SPAM by spamming spammers, ie, it sent back opt-out emails to all spammers who sent spam to Blue Security's clients.
But, Spammers targeted Blue security with a Denial-of-service (DOS) attack and brought down the entire site and its network.
So, Blue security decided to close its business and shut down its service for good.
Here's more about the incident from InformationWeek.com: >>

The anti-spam venture embroiled in a denial-of-service attack that brought down millions of blogs two weeks ago has thrown in the towel. Wednesday morning, Israeli-based Blue Security posted a message on its site -- now offline -- that it is shutting down operations.
Blue Security, which debuted its spam-fighting service last summerand built up a user base of more than 500,000, decided to wave the white flag after its servers were knocked offline by an aggressive denial-of-service (DoS) attack it claimed was launched by a deep-pocket Russian spammer tagged as "PharmaMaster."
May 3, in an attempt to get out the word about the DoS, Blue Security repointed its domain to an unused blog on Six Apart's TypePad blogging service. Within minutes, PharmaMaster attacked the blog with another DoS, which brought down Six Apart and left millions without access to their blogs. Blue Security's domain name service provider, Tucows, was also hit with a DoS and knocked offline for several hours; Tucows going down took thousands of Web sites it hosts with it.
Wednesday, Blue Security said it had to give up because it couldn't sustain the fight against spammers. "Several leading spammers viewed [us] as a strategic threat to their spam business," Eran Reshef, Blue Security chief executive wrote in the message posted to the company's site.