I've heard reports that if you want to be sure your bag is not lost or tampered with, all you have to do is declare and check a firearm.

This supposedly works for most domestic US travel (but is a bad idea for travel to NYC and is not wise for travel to/from some other countries), according to accounts at http://www.quora.com/What-are-common...er/Ryan-Lackey and http://deviating.net/firearms/packing/.

The idea is that if your luggage has a firearm inside, no one is going to tamper with it during travel -- so if you're traveling with tens of thousands of dollars worth of camera lenses and want to make sure it gets there, just toss in a weapon (and spend the extra time at check-in to get your luggage properly screened and loaded).

I haven't tried this myself, but the account I read suggested that you don't even need a "real" gun -- an unloaded starter pistol supposedly works just fine for TSA purposes and has the advantage of not being a "firearm" in the eyes of civilian authorities at many destinations.