What to do about nothing.....

The most nerve racking thing to me is when I'm at work and there is nothing to do. I mean I have to look busy, and I try. I'm good at finding something to do when the boss comes around. Unfortunately sometimes there is just NOTHING to do!! Does anybody hear me? Am I the only one who feels guilty for having nothing to do? One day I did computer in services. The other day I found little things to busy myself with, but still found myself with excess time. To make matters worse, since everybody knew I didn't have anything to do they all hung around me. I mean it's like I'm a social magnet on those days. Somebody finds something to talk to me about. I feel bad enough not working to begin with. Then to add obvious lounging around with co-workers to the equation well its just criminal. I go check on my patients but they are doing the same thing they were 10 min earlier. I pretend to look busy but every body knows I don't have squat to do. They just wait for me and continue on these meaningless conversations. We talk about the weather. We talk about their kids. We talk about how busy we can be at times (though at the moment we're not). We even have the audacity to wish for something to do (though we don't wish ill on anybody). I tell them that I work much harder at home, and many times I do! They just laugh.
One lady has it down to a science. She can sit for hours around me doing nothing. As if by instinct, she points to the plate of apples and peanut butter I have set out for my fellow do nothingers. I pick it up and bring it to the break room. Suddenly she is quite busy and gone all together. I know that I must become busy. An important person walks through looking well, important. "Only two patients" he observes. I nod, "I'm working on my computer skills learning" I smile (trying to look busy). He walks on. I want to scream "None of us are doing squat!!" But I restrain myself. Suddenly the group re assumes its position around me again with incessant chatting. I can't focus on my computer skills. I do them, but with half a brain. The other half is listening to incessant chatting of my coworker friends. I love them all. I love to hear them talk for hours on end. Its a never ending paradox. I feel guilty for being friendly and visiting with them.
What do you in Internet land do when your not busy at work? How do you stay a good worker when there is no work to be done? Am I just square? I want to be a good worker. I just don't always know how to do it.