When I taught in Philadelphia's Public Schools, I saw thousands of iPod-carrying city-folk. Business-types, average-Joes, and students all had 'em. Travelling the city via mass transit (I highly recommend if you're the green-conscious type), it seemed to be the way to make time go by faster, or at least more enjoyable.
Now, why wouldn't every music teacher you know, own an iPod? I'll tell you why! Because they're expensive! But, alas, I finally bought myself one, ripped all my CDs onto it, including the Norton Anthology of Western Music CDs, and a bunch of well-known violinists, cellists, bassists, etc. (anybody want to recommend one or two remarkable viola soloists?).
Now that I have one, I'm finding all sorts of educational uses for it. I'm not talking about giving each student one, or even letting students use mine, but those are awesome possibilities if the budget allows for projects like that. I'm talking about being able to plug into a PA system and improvise over a rhythm section. What about having a portal music player even when you don't have a permanent classroom (or one without electrical outlets)? It gives me a chance to practice my conducting, often while I'm driving, listen to educational podcasts, while I'm driving, preview new works from sampler CDs, while I'm driving...you get the point.
This is definitely not the last time you'll hear about this topic. I'm still very "newbie" when it comes to my iPod, so I'll be looking for more ways to use it during the school day (for *coughs* educational purposes...troublemakers)