I too have gone through long periods in my career where I feel I'm getting paid to surf the web (Can you tell this is one of those periods?). Hurry up and wait seems to be a fairly constant theme in IT work.
I've calculated that about 20% of my time is spent doing interesting work. Developing new applications or processes, learning new languages or technologies and the like. The rest is fairly mindless and/or tedious. And of course there are stretches where all I'm doing is waiting for a fire to put out.
Motivation is hard to keep up during those stretches. You start to feel that since you're doing nothing, that nothing you do matters. Last year at this time was the worst for me. We were in a Y2K development freeze, so there was absolutely no work being done at all. Of course we knew Y2K was absolutely irrelevant to our applications, but management insisted on a November - March freeze.
You know it's gotten bad, when you start to resent real work when it finally does appear. I started structuring my days around my personal tasks and looked on work as an interruption in my routine. Updating my personal web page, or emailing my friends became priorities.
Fortunately, I recognize when these things have gone a little too far and manage to find some piece of code that needs tweaking, or an application that could use a major overhaul and convince my boss to let me do that. Of course, I still reserve some time for important tasks like posting to K5.
A bored programmer is a dangerous programmer.
I used to be disgusted, now I try to be amused