The Firepod is a nifty new gadget that lets you charge devices in your car via a USB or Firewire port. Not every audio player supports USB or Firewire charging, but (we believe) that all generations of iPod and iPod Mini do. iRiver H1xxs do not support USB charging, but the H3xxs do. Go figure. [Via Engadget].
It should be noted that Boxwave is making it possible to charge the 100 series via USB:
http://www.boxwave.com/products/easyfinder/products-for-iriver-h120_354.htm