Be prepared when you give your two weeks to be shown the door immediately, WITHOUT THEM PAYING YOU for the full two weeks! They will cut you out immediately even though you have a deliverable within those two weeks and are fully prepared to dedicate excess hours to making it a winner for the client.
Yes, that's right. They have an emotional reaction and are even willing to tank a major effort you have just started to work on, hurting the company's chances of survival. This was after I was begged to stay, and told "we need you, we need you!" This kind of behavior makes me wish I had left when I first thought about doing so.