How about " 'Sup?"

For some reason, I receive all the emails at work for a random email address that is supposed to be for general questions, possible partnerships, etc. But most are spam. And the easiest way to tell is by looking at the salutation. A few recent ones:

Dear Sir:
Hallo!
Hi, dear.

And my personal favorite, Hell. (Clearly they forgot the "o," but still. Classic.)