When I'm home, I'm lazy until I start working on something.. after starting, I can take hours or even a full day (24hrs) on it (taking 10 min pauses every 5 hours, of course).
And I usually start working faster when I'm over pressure. For instance, if I don't have much time before I have to finish whatever I'm doing, I won't be lazy to do it and will work faster.
I don't have concentration problems, and I can pay attention to more than a thing at once (i.e.: writing something to a friend on MSN and saying/listening to someone near me). This often piss my parents off because they think I'm not paying attention, reading and writing on the computer, "so repeat what I've just told you", and I always repeat it perfectly
But I have a problem, I'm very perfectionist and I always check everything I do a lot of times. Sometimes I get myself reading something I've written more than 10 times before actually considering it finished or sending it (if it was a email for example). And I almost never change anything, just read it all over again.