Ran into what appears to be a great service: http://www.stuffbak.com
They provide for a nominal fee serialized stickers to place on our HTs - and about anything else you want to protect.
A person who finds your stuff calls a toll-free 1-800 number, and reads off the serial number. The operator will offer a freebie/gift set of their own ID stickers to use ... and/or you can place a "cash reward" on any item you wish.
Reader's Digest magazine recently intentionally "lost" thousands of wallets - each with 50 bucks in local currency inside. Believe it or not, 70% of the U.S. lost wallets were returned by their finders...People *do* have honest streaks in 'em!