You lose benefits and the possibility of taking legal action against the (former) employer if you quit.
Even in "at will" employment states you can sue for unlawful termination.
In this situation it would add up to 'constructive dismissal' so he wouldn't necessarily lose any rights.
What do you want by 11PM? A design?
Really, you want the whole thing completed?
Is this some kind of a joke?
(Depending on relationship) Walk out the door without saying a word, "I quit," or even better, just stand up and say, "Everyone who thinks this is absurd walk out the door with me right now."
Why: What I've learned is that employees ignoring an unreasonable boss sends a rapid signal to upper management to get rid of the unreasonable boss.