No iPods? Why?

I began thinking about students getting lost in their electronic gadgets in the middle of class. Is it annoying to you, the teacher? Absolutely. But why is it annoying? Is it because they're not paying attention to the material, or because they're not paying attention to you? The first thing we should think of when asking them to pay attention is say, "Why?"

For example, if I were teaching a physics class, and I say "Put away the iPod," the students would usually do it grudgingly. But if I make it clear in the first place, saying "iPods are not allowed, because if you pay attention in this class instead, you will begin to see how physics is all around you in the world and how spectacular it is, and possibly you'll even learn how your iPod works," then it gives them more of a motivation--more of something to look forward to in my class.