"What is ZipCharge?
The definitive way to power all your portable devices when on the move. Charging this pocket-size stick of dynamite for just 10 minutes will store enough power for 10 hours talk time on your mobile or 20 hours play time on your iPod."
Apparently a 1 min charge will give you enough power play with your ipod for another 2 hours, and a full 15 min charge will give this device enough to fully charge your smartphone. Not bad if your forever running out of juice.
Been looking at these for a while, but at £50, it just wasn't worth the risk. I might consider giving it a try now :D