The most cost-effective way to get more from your 'Pod may be to treat yourself to some better earphones. You'll hear the difference with a $50 pair, but you can spend as much as $1,000. Top-shelf phones often require more power, however, so you may need a separate headphone amp to get your money's worth.
Are noise-canceling headphones worth the cost? Perhaps. Around-the-ear models with antinoise technology work well to dampen steady noises like airplane drone. But "in ear
canal" phones - like the Shure model, right - can be nearly twice as effective and require less power to deliver high fidelity. They do take some getting used to, however, so if
you can, try them on before you buy.