I am out of usable space on my Ipods

I'm currently using a 160GB Ipod (A-P) and another 60GB Ipod (Q-Z), both of which appear to be maxed out. My most recent download is the new Flaming Lips 24-hour song 7 Skies H3, which is almost 4GB in space and pretty much capped me out. How long will this new single take me to complete at work....?

I guess we will find out.