Solar phone charger

if you're a bit nifty you can make your own. (why not attach it to a bus window and charge up while travelling?)

As I can't post a direct link to the site, check out - instructables.com and search for DIY-Solar-Phone-Charger-5-Portable-100-Batter/?ALLSTEPS

The site also offers,inter alia, 'Assembling a BootstrapSolar Chi-qoo Solar Battery Charger Kit'