I'm a big fan of what I consider to be engineering marvels of the world. Big public works projects that may or may not no economic sense in a pure cost benefit way but add to the economy and a wonder to see. The ones that make me step back and go "Wow - how did they do that!?". Hoover Dam, Panama Canal, big bridges and the Thames Flood Barrier (to name a few).
The Thames Flood Barrier protects London from flooding. I really want to know how they did it. Unfortunately, while I've taken a sightseeing cruise out a few times I've never made it to the information center. And it doesn't seem to be a big sightseeing landmark.
Today's tip is to divide everything up between bags. When packing for your trip, assuming more than one bag is involved (either because of more than one person or you take more than one bag by yourself), make sure you divide everyone's clothes between all the bags.
Why you ask? That way, if a bag is lost, damaged or stolen, no one person is out everything.
Be careful how you divide things up too. Don't put everyone's casual clothes in one bag and underwear in another. Think full outfits. This way if you only get one of your bags you still have something appropriate to wear.
Bonus tip: if you are checking all your luggage - it wouldn't hurt to pack a spare set of underwear in your carry-on. Just in case *everything* goes somewhere different than you go.