@Anahata, many router will work forever without a problem, I was trying to counter the perceived wisdom that routers never cause a problem, they are often a problem, especially the Belkin model that started this discussion.

@Tootler, the variation is most like due the amount of substance your asking the radio waves to penetrate. To take a worse case example, if a house has a brickwall down the centre and the router is downstairs at the back on one side of the wall and the lap top is upstairs at the front on the other side of the wall the radio signal probably has to travel through brick for 5-10 metres. moving the computer 1m away from the wall will reduce this to less than 1m - that could be the difference between no signal and full signal.

Simon G