fuck this job.com

Why is it that your bosses never once tell you how much (if at all) they appreciate your work till the day you hand in your notice? And why do they then proceed to give you more work do to in that last week or two than you have done all month?
It's probably some twisted sort of revenge, but what I don't get is why they would think that I'd do that work well? I mean, I have a new job. I don't need a reference and if I ever do, I'll not be asking this loser and he knows it. Plus, my new employers know that I wasn't happy here and the role is completely different -- so he can tell them how awful I was and it wont make a difference.
As for the clients, I smile and let them know (subtly) that since this is my last week here the project must be low priority for them to entrust it to me...Of course I never actually say that so no one can blame me later and if they do, it'll be a case of their word versus mine. So why? Do they really think I'm at the stage where I'll get stressed over this sort of thing?
Essentially, vengance is mine...muwaahahahahahahahahaha!
But full marks to the idiots for trying.