No reader question, this time. I just want to step onto my soapbox for a moment.
Alicia Sanchez and her 11-year-old son Carlos set out for an overnight camping trip in Death Valley. Five days later rescuers found Sanchez badly dehydrated and Carlos dead (click for details). It's possible she depended too much on her car's GPS.
That's a real danger.
I love GPS. It's great to see your actual location on the map, and spoken directions are a lot safer when you're driving than written ones. But these gadgets don't know everything. They don't know road or traffic conditions, or the advantages and disadvantages of one type of road over another.
Anyone who's depended on GPS enough has received bad advise. They've told me to take a slow and difficult route because it's a mile shorter than a fast and easy one. They've advised me to turn left at a dangerous intersection when a slight detour would let me turn where it's safe. Two different GPS systems insisted that the same major thoroughfare was a one-way street (it isn't).