This is part of the experimental homebrew iPod charger testbed. Sure I could buy an iPod charger, but with a budget of exactly £0, it's fun to experiment. It seems the 'pod needs to see 2v on the data lines before it'll charge from the 5v on the power line. A couple of resistors to make the 2v and it works a treat. iPod charged, DIY style. I'm over budget by about 20p for the resistors tho...