Hacker finds way to (re)use Emergency Broadcast System
abclocal.go.com
abclocal.go.com
It may seems odd to "hackers" that the system is so simple, lacking encryption, authentication, or human checks and balances, but thats kind of the whole point. If it actually needs to be activated, nobody is going to be around to press the big red button or verify encryption keys. They will all be home evacuating their families.
http://anonymous-lulzsec.com/entries/encoders/same_enc-same_...
I think anyone thinking about attempting this should read the story about the boy who cried wolf. If anything you reduce trust in the emergency broadcast system. This would be very bad, especially if a genuine emergency shortly followed a B.S. hacker broadcast