I love the iPhone, save for one thing. It sits on my desk every night, right near my computer, and the speakers I've got hooked up to it. And every 15 minutes, when the iPhone checks email for me, I get that buzzing -- the sound of radio interference flying across my speaker wires. And almost every night, I have to jump out of bed angrily just to shut off the speakers and stop the buzzing. Little did I know, all I've ever needed was an empty can of Red Bull.
Yes, someone has fashioned a "shield" out of an emptied and carved up Red Bull can, and supposedly it works like a charm -- just fashion it around the dock that came with the iPhone, use a little doublestick tape to make sure it stays on there (and I would maybe put some around the edges, too, so you don't slice your fingers open every time you pull the iPhone off the dock), and no more buzzing sound.
The maker does wonder if it would affect the actual signal of the iPhone at all, but it hasn't so far. If you've got a Red Bull can around to cut up and are driven as nuts as I am by that buzzing noise, here's your makeshift solution. The other option is to buy speakers that don't buzz, of course, but this seems a lot cheaper.