Blutracker is an ultra small Bluetooth GPS locator. It has a range of over half a Mile, the battery lasts for over 2 months in between charges, it has a full GPS engine and motion detector. There are absolutely no service fees!
Most pets that are lost, are within a couple of blocks from your home.
Track your kids in large playgrounds, parks or in your neighborhood.
Discover the exact outdoor location of the BluTracker within 10 feet at any time.
Built in motion detector notifies you if your item is moved or missing.
Also the Engadget link:
They claim an unobstructed range of 2500 ft for the tracker, it doesnt record GPS coordinates but it is water resistant and looks like it would be a great lost drone tracker. Only weighs 16 g.