My wife just lost her tiny Swiss Army Knife, owned for 20+ years, thanks to security at Las Vegas airport. One careless moment, in countless dozens of international flights, normally it gets transferred to hold baggage before the trip to the airport - but a stressful morning running around sorting things out, too much on her mind, and it's so small it's easy to forget about. No value to it, other than that which gets transferred via 20 years of faithful service. The TSA agent was really friendly, and quite apologetic about it, but there's no arguing with them. The fact that I could do more harm with my litre bottle of whisky doesn't come into the equation.
Currently in my pocket I've got a rather nice for its price, 3 bladed (non-locking), wood handled Farmer's knife from Puma of Germany (although this is one of their bronze badged models made in China, hence the price - less than a tenner. I've got a beautiful olive wood handled Laguignole knife and corkscrew which does sterling service for French holidays, taking the cork out of my lunch with a lovely flourish, it also cuts cheese, meats and fruit beautifully. I've got more SAKs than is strictly healthy including a lovely black Director's knife that was a gift from my father, a couple of Japanese Higo knives, one with the bent brass handle and one with a nice wooden grip. I've got a fantastic Spyderco locking knife, the blade smeared in vaseline, that is my old diving rescue knife and cuts through rope better than any other knife I've ever used - I bought it before they released their 'salt' blades. Then I've got my Flexcut carving jack, which rather like the legendary Gurkha Kukri never seems to get sheathed until it's drawn blood...