Since Bihnions are very practical and have exacting standards for gear, I thought I'd throw out this question - where would I go for safety lanyards? Something with a reliable breakaway feature.
The reason I'm looking is that for our summer trip, I'm thinking of giving the kids each a lanyard, with a TB whistle and a small light (Photon Micro). I'm thinking it would be handy for when we are actually in transit (e.g. on the plane) in case of emergency, or in case we get separated. They could wear it under a midlayer or hitched around a belt loop and pocketed, to avoid getting snagged. Otherwise they can keep it in their Travel Tray - I am planning to assign one to each member of the family.
(I wonder if it would be odd to carry a pitch pipe? How big is that? I seem to recall there were villages in Spain that had a set of coded whistles, for communicating between mountaintops. I've tried teaching my kids to respond to the sound of the Star Trek bosun's call, but they ignore that, as they do all my signals that it's time to leave. ;P)