If you are out and about with a laptop it is often difficult to get a good signal. One technologist has come up with a simple way to improve any signal which might be in the area. Just use a metal baking tray to try and collect and deflect any available signal to your laptop.
For a more professional approach you might buy one of these USB Wifi extenders.
This will just plug into a USB port on your laptop and with a 5 meter cable can be moved to a position to give maximum signal strength. The unit is available with a pole mount kit and I have recently used on to provide a wifi signal extension to a caravan.