Macworld recently ran an article testing various theories surrounding WiFi. Most of them are not that surprising except for the remarkable increase in range with a home-brewed tin foil antenna booster. The one question I have is how well that booster works in a 360 degree survey. It looks like it would be great in one direction and dramatically decrease range in the other direction. If you've centrally placed your antenna in your home (like you should) I'm not sure how useful this is.