I wrote the other day that the first thing that comes in mind when you mention luggage and airline in the same sentence is "lost luggage".
Whilst airlines and airports have arguably become better at tracking, here's a technology that might relieve the stress of those of you concerned about the whereabouts of your cherished luggage: Trakdot.
Interestingly, the device doesn't use GPS, relying instead of GSM signals and your phone (via SMS or data for the app). This means that the closest geo-location you'll get is the nearest cell tower—some might find it not sufficiently precise. Though at least you should be able to tell if it's near the right airport, which is sometimes more than enough to make you happy.