digital art can make me feel this way, especilly when i end up doing more computer crap just to get to the point of making art :(. get yourself a nice big wall and throw some paint on it ( i mean your own not the side of the local store as im not sending bail money)
Drawing only becomes boring to me when I've drawn enough for a certain period of time. When this occurs, I usually do other things until I feel like drawing again. The same thing happens when I'm reading, too.