Maplin have done these for years
Hooking your laptop into your car’s battery for a little on-the-road juice isn’t the safest of options. So battery business Duracell and IT peripherals firm Belkin have launched competing in-car USB chargers. Duracell_USB_charger Duracell's USB Charger glows blue when ready Duracell’s USB Charger is described as one of the …
Amazon have these in stock today. I've been waiting for these since my cigarette lighter socket is in such a stupid place!
The Maplin one is HUGE