We have started using a GPS in Norway to explore on our road bikes and found it really useful. The idea of doing a long cycle ride with a GPS appeals so when I discovered that I needed a new front wheel because my rim was really concave we decided to order a new wheel from SJS Cycles with a SON Dynamo hub built in.
We then bought a Busch and Muller 'E-werk' which allows the dynamo to have USB output and to change the voltage to charge lots of different things. So far we have used it effectively on mobile phones, USB and also an Android tablet.
The freedom given by the use of a GPS is amazing. It is especially useful when entering a city because thanks to the amazing free maps from Open Street Maps which you can just load on your GPS you get a perfect turn by turn guide to reach some of the most difficult parts of a city.
