I know at least one person who would welcome this.
In Italy, they are trialling a GPS system that is designed for the blind and partially sighted.
The system uses a Bluetooth Mobile, a bluetooth GPS unit and software.
The software has two controls. One that tells the user their exact location, and another that phones a call centre, and the person can ask for help. The operator can then help guide them to their destination..
http://news.bbc.co.uk/1/hi/technology/6458005.stm