Name: HangTimer for iPhone
What it is: An iPhone application that records how high you're sailing above the ski slopes or any other surface
How it works: Software downloaded to the iPhone uses the device's accelerometer to measure gravitational forces and acceleration, calculating weightlessness. It works best when worn inside a jacket and near the midsection. While it reported nothing when I hopped around our office (HangTimer for iPhone is designed to capture the wearer in freefall), it worked great when I leaped off a 4-foot cabinet, calculating I spent 0.77 seconds in flight.
The good: After a run down the slopes, see how much air you caught and how fast you were going.
The bad: A fall could take a toll on your device.
Cost: $10 at iTunes Music Store