Best Technical Security Conference?

Jeremiah Grossman recently did a short podcast on Help Net Security on his top security conferences. He didn’t name one as the best, because each conference caters to all different sorts of people. Some are highly technical, some are more business related, and some are more underground.

My question to you is which conference is best to gain technical knowledge on security? If you were only able to go to one, which would it be. Please vote below, and provide a reason for why you chose it.