I fly quite a bit around with my rifle, and just picked up this luggage tracking device. I'll put this in my Pelican case along with my rifle, and it's designed to send me a text and SMS when the plane lands, so I can be sure of where my gear is. I've only once had an airline misplace my rifle, but I expect should provide some peace of mind when traveling.
http://www.trakdot.com
I just activated it today, and so far it's picked up that I'm close to my own airport: