Yes. It's not particularly good for the battery to have it plugged in at all times, but it won't damage it any more than leaving it plugged into the wall will.
do you mean you want to leave it connected all the time?
the question would be why? charge it, unplug it and GO!
i rarely plug it into the computer and only to back it up, generally plug into the wall when i go to bed, unplug in the morning and i'm off...