I can appreciate that. In my case however, I record the BBC Radio One Essential Mixes every week, which is a 2-hour live broadcast (sometimes longer!) showcasing the best DJ talent in the world. I record each broadcast and have every single show since 1993, with the exception of about 6. So, at ~170-180 MB per 2-hour show x 52 weeks in a year x 11 years, add on all the extended shows and special shows, you're looking at about 120 GB right there. This doesn't include my weekly Digweed KISS FM sets, nor my actual music collection, which is over 100 GB on it's own between MP3s and audio CDs.
So in my case, I don't need all my music with me, because with my Essential Mixes, although I do like listening to many of my favorites on a regular basis, I am for the most part collecting them and do not require every single one on my iPod - after all, with almost 600 shows, equalling probably 1500+ hours of music, that would take me a while to listen through! 😉 I am mostly concerned with having my actual music collection on my iPod, and even then, as I said, 20 GB is good enough for me - I don't need everything, just my favorites (which adds up to a lot of music as it is!) 😎