Car chargers for USB devices are pretty easy to find. I was in Gamestation and picked up a BigBen charger for Sony PSP, Nintendo DS which uses a USB socket on the transformer. Great, I thought, I can just plug a USB->microUSB cable into that and charge my phone.
Mobile phones use a trick to see if the charger actually coming from AC or some other source. This is to protect the device so that that phone won’t try to draw too much current. Thanks to an old university friend I found the solution. So all I did was prise open the case, melt a drop of solder between the two data lines (the middle two) and then snap it all together again. There is a chance that this will draw too much current but it is rated at 1.3A and the phone requires 1.0A, and it appears the logic in the phone itself ensure it monitors how much it is drawing to something around 500mA.
It’ll be fine!