Workshop Connectivity Issue

[Compnerd]

Our team this year had to rent out workspace. The workspace is much better than the schools classroom we had last year, however, the workshop has no internet connection. The Bread Company (approx. 300 feet away) has offered to let us use their wireless internet connection. However 260 feet is too far for the wireless signal to travel. We are trying to think up of some ideas to be able to be able to extend that range. Some of the ideas that have been mentioned are "Cantennas" which are basically potato chip cans with a wire inside acting as an antenna. Also, i thought about using a "repeater" which would be placed between the workshop and Bread Co. each of these have their advantages and disadvantages. I have done some research, and found that the signal will travel roughly 150 feet from breadcompany. A normal 102.11g router will broadcast 300 feet if outside without walls blocking the signal. The only signal we pick up is the post office's wireless next door, and that's not a possibility to use. Please post with any comments/ideas.