Well, i have a soulution for you!
This USB charger utilises 2 standard cellphone batteries to charge your iPod, much more storage than a usual USB charger.
N.B. To construct this project, you will need a mild understanding about electronics, how to read schematics, solder etc.
I am not liable for any damage that may occur to your iPod from using this project.
Li-ion batteries can be potentially dangerous. Handle them with care and NEVER short-circuit.
Step 1: Parts & Tools
2 Nokia (or equivalent) Cellphone batteries
1 DPDT slider switch
1 7805 regulator
1 Small heatsink
1 Female USB connecter
1 330 Ohm Resistor
1 Small red LED
A box to put it in (I used a small DickSmith one)
1 Small set of male/female connectors (I used old style nokia charger M/F connectors)
Lots of small wires
4 47k resistors (optional)
Soldering iron and solder
Step 3: How it works
When the switch is in the other position the 2 batteries are in series, with a total voltage output of about 7-8v. This then feeds the 5v regulator (the 7805) which puts the voltage down to 5v.