Highly dependent on the individual.
Layne Norton has talked about how with genetic lean individuals, there is a tendency for the metabolism to elevate and burn off excess calories above maintenance - but with people who tend to be on the fatter side, any excess is immediately stored as body fat.
Of course, as others have mentioned, glycogen stores will come into play here - if you are depleted, you won't be converting carbohydrates to fat (which rarely happens anyways).
On the flip side, if you have been dieting for a long period of time, your body will be more primed to store fat so you have to be careful about huge cheat days during diets - there is a reason people slowly increase calories (ie reverse diet).
As far as a daily limit, part of that has to do with digestion. Unfortunately, high amounts of dietary fat can just sit in the intestines and move very slowly until all has been absorbed. So usually, unless you are doing extremely insane things with the amount and types of food you are eating, most all of those calories will be absorbed. And once absorbed, there's really only two options: burn or store. I don't think it's possible to simply "piss them out" as some people claim. If your metabolism doesn't rise up and burn them off, they will get stored (usually as body fat).
My guess? Let's say you have three extra large pizzas, three bounds of bacon, a jar of peanut butter, a dozen donuts, and a few beers and sodas. Let's call that 30,000 calories. You absorb most of it. Your body only elevates and burns around 4-5k. So let's say you have 25k excess. But this absorbs in your intestines over a two day period. So over two to three days, you gain about 5-7lbs of fat.
Pretty insane, but I think it's possible under the right conditions.