The most extreme "Castle doctrine" or "Stand Your Ground" law in the US currently is the 2005 FL law, as summarized by the NRA:
The "Castle Doctrine" simply says that if a criminal breaks into your home, your occupied vehicle or your place of business, you may presume he is there to do bodily harm and you may use any force against him.
It also removes the “duty to retreat” if you are attacked in any place you have a right to be.
Furthermore, this law provides protection from criminal prosecution and civil litigation for those who defend themselves from criminal attack.
Under prior FL law, if you reasonably believed the intruder was a threat to your person, you already had the right to shoot him.
So what the Castle doctrine adds is that you no longer need to believe he was a threat to your person. You can shoot him simply for having:
(1) unlawfully and forcibly (presumably if you leave the door open and someone simply wanders in, that's not "forcible")
(2) entered or is attempting to enter (so you can shoot him off the windowsill, as it were)
(3) your home (including a covered porch, tent, hotel/motel room, temporary lodging, even a guest room in a friend's house), or occupied vehicle (car, truck, camper, etc).
The law also has some provisions about what you can do if you are attacked in a public place.
After reading the law and the very helpful analysis linked to below, I think it is basically a reasonable and good law. (Though it seems like a poorly drafted law - the Florida legislature doesn't seem to know much about writing clear, unambiguous statutes - but the courts will figure out the ambiguous bits.)
Now, let's be clear, the FL law makes it quite clear that you can now kill to protect property. Even if you know for a fact that the person climbing back out your window with your TV set (or, for that matter, empty-handed) is not and never will be a threat to your person, you can still shoot him dead - just for having broken and entered. (However, I think you still can't shoot him as he runs away down your driveway.)
I'm not willing to say that a life is worth less than a TV set. But I think that, after this sort of Castle doctrine gets applied for a few years, people will tend to change their behaviour so that the choice between life and TV set won't come up that often.
http://www.floridafirearmslaw.com/florida-selfdefense-law-analysis.pdf#search=%22florida%20castle%20doctrine %22