Do you own your own company, and have company vehicles? If so, you may want to look into vehicle tracking systems. Knowing where you employees are while on company time can save you money in a bunch of different ways. For one thing, gas prices are pretty high right now, and if your employee is using the company vehicle to run personal errands on company time, you have a right to know bout it so that you can put a stop to it. Tracking your vehicles can also insure that your employees are being efficient.
Some people may think this is an invasion of their privacy, but I don't agree with that. If you are on the clock, than your boss has a right to know how you are spending your time.