Meritline.com offers this iPhone / iPod Car Charger for $3.99 with free shipping. It features support for iPhone, iPhone 3G, iPhone 3GS, and iPod models with a dock connector. It also has a spare USB port for charging other devices. I use this charger and it works like a charm for me, I know others have had some problems with it. But for $4 might be worth it to check out!
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