Well, on the going deaf part, I think the main thing is don't turn your iPod up to deafening levels. Seriously, its really about not blasting them. The easiest way to do this is to watch and make sure you don't turn it up too high *and* to get headphones that deaden the sound.
Etymotic at http://etymotic.com is a little bit of a niche brand, but audiophiles swear by it. There is a great site called http://headroom.com that explains all this. YOu can get these by the way at http://discountheadphones.com.
The 6i are expensive at about $100, but they are amazing in terms of sound quality. If you really go crazy, the $200 Etymotic 4's have beat $20,000 speakers in blind hearing tests.
I actually got both of these and can say folks are usually incredibly amazed. Why is this? Well, Etymotic is actually a hearing aid company, so the actual speakers fit inside your ears. Makes them phenomenal for working out at the gym or on an airplane. They reduce the noise by 20dB (Ask Jeff what that means, but it is essentailly 99% quiet). And they are super tiny as well and not bulky like the big Bose ones.