MAKE has a link to a metacafe video where a lady demonstrates how to use a soda can or two to boost your WiFi signal. The instructions are simple, and all you need is a marker, an empty pop can or two that have been cleaned out, a hole punch, and something that can cut the cans without bending them too much.
You start by removing the tab, making some markings, cutting the can in half from top to bottom, punching a hole for your WiFi router/AP’s antenna, and then putting the antenna through the hole. There is a recommendation of using a marker to make the cans uniformly black, but I don’t think that matters.
In the end, I don’t see this hack giving you a signal boost no matter what you do. Directional control of your signal, sure, so it would allow you to keep your signal in your house, or even direct the greatest part of the signal in the direction where you work most often, which might give you some sort of a boost, but that’s about it. Then again, I am not a radio signal expert, so I could be wrong, but I am not completely devoid of understanding of the basic concepts involved.
Boost Your WiFi With A Soda Can [via MAKE]