If you think stock cars are fast, you should look at their onboard computers.
Telemetry is the remote collection and measurement of data. It usually involves some sort of wireless broadcast. Of course, remote data collection is important in many fields -- defense, medicine, even agriculture. But it's rarely more exciting than in stock car racing.
A stock car has a computer that collects and broadcasts the car's vital statistics to a central computer [source: NASCAR]. The broadcast uses a wireless radio -- so it's basically a souped-up PDA that automates messages from the driver.
