Reply-all e-mail storm hits State Department
Found on Associated Press on Saturday, 10 January 2009

Many "reply all" fiascos result in mere embarrassment, but American diplomats have been told they may be punished for sending mass responses after an e-mail storm nearly knocked out one of the State Department's main electronic communications systems.
He said the result was "effectively a denial of service as e-mail queues, especially between posts, back up while processing the extra volume of e-mails."
MTAs have an option to set a limit for CC/BCC for some reason. For the admin, it's just a simple setting and it won't happen again. Plus, deactivating CC might also be a really good idea since most people are not aware of the problems they create by mailing the latest "joke" to everybody they know; pumping all your friends addresses through the net raises the chances for them to get spam drastically.