Find MyHeadset, part of the Plantronics Spokes portfolio of software solutions, is the answer. Most headsets are found under car seats, in pockets, or on a messy desk. For less obvious locations, acoustically locate your headset by sending it a tone so you can hear where it’s hiding. If your headset is out of Bluetooth® range (33ft/10m), or is powered off then try the Backtrack™ activity log that maps where it was last in use.
Bonus: If you have the latest Android 3.0 or later, you will see an on-screen headset battery meter in the notification bar.