I haven't done much today with my computer. For about 8 hours I just had itunes running and was playing songs at work. Now, I am on iChat and a few other apps surfing the web and communicating. I am not saving anything or downloading anything. Yet, despite all of this, Time Machine starts every 10 minutes or so and backs up about 3 GB on average. I don't know why this is. I haven't done anything. Does anyone know what the problem may be?