Iphone 3g will not find my home Wi-Fi network?

Hi. I have an iphone 3g which has always connected OK to my home Wi-Fi network. I have not changed anything but now it doesn't even see the network. My iphone sees other Wi-Fi networks in friends homes, and my laptop picks up mine just fine. I use windows 7 on my laptop. This is driving me mad so any help woud be greatly appreciated.

You could try changing the channel of the Wi-Fi.
A friend of mine had a Macbook that couldn't find ours and changing the channel to 9 fixed it.