I read this a year ago. A british guy in my company spammed the whole office w/ it, as we were an American firm w/ a lot of British people in it. Anyways, this is going from memory, but I think it'll suffice.
American Actually gets Sarcasm:
John was in London on a business trip, loathing the usual London rainy weather when a colleague in the elevator said, "Morning. Nice weather, yeah?". It took him a few minutes, but John eventually understood that his colleague actually didn't think the weather was nice, but that he meant it as a joke.
John says that now back in the states, he's using sarcasm on a regular basis to lighten up the mood with his Ameriacan friends. "I was having a cook out with some buddies last weekend, and I totally burned the burgers - almost beyond recognition. Not thinking twice, I put one down on a bun, handed it to a friend and said, 'hey - nice weather' ".