The Nike + iPod kit is an accessory for your iPod Nano which allows you to track your walks and runs in an amzing new way. It consists of two parts a sensor that fits into Nike+ shoes (or third party pockets which are designed to attach the sensor to your shoelaces) and a receiver tha plugs into the bottom of your Nano.
A new menu for the Nike+ appears in your menu and it gives you several workout choices - time, distance, calories, and the open ended basic mode. When you select a mode and a playlist to listen to and your workout will begin with a voice announcement. The iPod will then begin to track your speed, time, distance and calories burned.
When you press the center button during your workout it will give you a vocal announcement of your current stats or you can set it to trigger a "power song" to give you an extra boost when you need it.
After your workout the next time you sync your iPod it will upload your data to the Nike+ website where you can see a visual representation of your speed and compare workouts among a number of other features.
I think this is an amazing value for under $30. I find it to be very motivational to get up and move. Recommended.