All of the biggest smartasses I've known have been ENTP (including myself). Though I think that is slightly different than sarcasm. Being a smartass is some combination of sarcasm and wit, while pure sarcasm is often not particularly witty.
In light of the responses thus far in the thread...a difference, perhaps, b/w NTJ and NTPs?
IA w/ Liquid, I think ENTPs (xNTPs) have the repartee thing down which I don't see as much with INTJs, but I do see the sarcasm in them. Maybe it's temporality that makes ENTPs smartasses rather than just purely sarcastic. Sarcasm often is delivered in a deadpan, and sometimes its best result is seen when followed with a pregnant pause.
My INTJ is very, very sarcastic....kinda a trademark. While, I can be sarcastic BUT I also love repartee (the quick volley back-and-forth, which he can't do/keep up with, cuz it takes him a while to formulate a response...but once it's out, it's golden). Also, I do more word play/twists/puns.
Sarcasm to me has that 'cutting edge' that makes it a particular brand of wit and humour. xNTJs got that down pat, while I think NTPs, esp. ENTPs, gloss the edges more, to make the joke palatable even to the receipient [if they want]. More 'fluffy'?
On the other hand I've known sarcastic people of just about every type. Not sure if there is one type that stands out.
Agree with this too. My ESTJ dad can be quite sarcastic as times.