Well, I suffer from the urge to jump to the next task before it is finished because I have already finished it in my head. I live by the rule: "No. Finish the thing you were doing first."
Otherwise, I think I am a very skilled multitasker. I can do work, listen to radio and keep an eye on web/mail etc. When faced with a challenge I can focus intensely. So intensely that other people can have a hard time reaching me sometimes.
Physics problems or logical quizzes need more of my brain than linguistics or general knowledge questions. Some answers just come to me without conscious effort.
EDIT:My SJ friends are jealous of me because of my mental quickness and the apparent ease with which I do it. They focus/concentrate on one thing, step-by-step but it takes forever for them to reach conclusion. Then, most often, it is one of my earliest and already scrapped (for several logical and correct reasons) ideas. I say that we have a multitasking skill that they havent got (and a model of thinking that surpasses theirs x10 when being creative) , but we must keep tight reigns on our minds so that we finish what we do and not wander off.
NT description says that we are able to focus intensely on any matter, and that we can seem like off-wordly to others....