Yeah I've tried a whole restore, with no success. As soon as my configuration page decides to work I've got 2 things to try:
1. change the channel to 1
2. change b/g to g only.
Have you got a friends iPod touch or iPhone to try? I had a problem when I first brought my iPod which was when I was in the states and the wifi wouldn't work and just said 'no wifi'. When I came back home to England where it was about 15 degrees cooler the wifi worked fine so I think the heat messed with mine.