A clothes designer from Germany recently introduced io-Jacket during Cebit last month. It is a hi-tech jacket that has a built in Mp3 player, cell phone and GPS. The GPS system uses GPSoverIP which uses the cell phone connection to store location data, which means that it will still be able to track when someone is indoors.
A video that shows how the jacket works can be found here (In German)
Excerpt from talk2myShirt