The Act of being completely shit faced. i.e. intoxicated, wasted, owned, shivased, and shmammered.
Oh my god dude I was so hammer stormed last night.
or
(Fist pump) "HAMMER STORM!!!"
Another term for gangbang, referring to many cocks.
Sheila's feeling sore today, she went out with the football team last night and got caught in a hammer storm.