We have seen a few of the wireless gadget chargers before here at Geeky Gadgets the latest one is designed to work with the iPhone 3G and 3GS, the AirVolt Wireless iPhone Charger.
The AirVolt Wireless iPhone Charger charges your iPhone via induction, and it comes with a receiver that you place your iPhone into and then it will automatically charge as soon as it is placed on the charging tray.
Simply slide your phone into the included receiver case, place it on the power tray, and watch in amazement as your phone charges wirelessly via induction. It works just as quickly as a standard charger and automatically powers off once your phone is completely charged.
If you want one, the AirVolt Wireless iPhone Charger is available for $49.99 from Think Geek.