If you're looking for a wireless charger may I suggest the Willy Willy case & Charger. Everyone knows of the Powermat wireless charger, but the Willy Willy is a better made product because it gets you that extended battery life you need for your Iphone 4. I got a good deal on mine because i found it on Amazon.
Here's the link:
http://www.amazon.com/Willy-Battery-Wireless-Charging-Cradle/dp/B005HR3JVI/ref=sr_1_1?ie=UTF8&m=A3VINPDK0TK1JI&s=generic&qid=1316559204&sr=1-1
Here's the link:
http://www.amazon.com/Willy-Battery-Wireless-Charging-Cradle/dp/B005HR3JVI/ref=sr_1_1?ie=UTF8&m=A3VINPDK0TK1JI&s=generic&qid=1316559204&sr=1-1
As an Amazon Associate, MacRumors earns a commission from qualifying purchases made through links in this post.