I've just read on Slavenka and Obi's blog about a new punctuation mark that is available for purchase. As it so succinctly suggests in the name, SarcMark, it's for letting readers know your sentence is sarcastic.
It might have been useful when a British woman said, "It's jolly decent of them to let me have a half share of my win,"as a court awarded her only part of the prize in a lottery after the winning ticket fell from her pocket and someone else claimed to have won.
Yes, that sentence could have benefited from a specific punctuation mark.
I looked at the YouTube commercial for the SarkMark and, at first, I thought the examples weren't actually sarcasm, because they were so unsubtle and heavy-handed. But when I visited The Online Etymology Dictionary, where there is a table of types of humor (from Fowler's Modern English Usage, 1926, I began to think the British woman's remark may have been sardonic rather than sarcastic, because they were possibly self-directed and aimed at dealing with adversity, rather than aimed at a victim or bystander and intended to wound.
The SarcMark YouTube examples certainly fit the definition of sarcasm at WordNet - expressing or expressive of ridicule that wounds.
I was thinking of downloading the symbol - it's only a couple of dollars - but now that I've become more aware of the hurtful aspect of sarcasm I'm not going to do so.