I think I would go for what one poster said also. Rip everything in lossless and store it on your hard drive, or pick up a 1TB external for about 90 bucks and store it there. It would take you so many days to listen to 64GB worth of music, you can just change your music in and out.
I will throw this into the mix however. If you're playing music straight from your ipod into some headphones or earbuds into your ears, then I would not bother tying up all the space with losless. I would go for 320kbps. Without high end equipment and very high end earbuds or headphones, you'll likely never hear the difference in quality. There is a difference, but it's going to take more than average gear for most anyone to hear it. Just a thought.