One thing I pretty much always have on me when I travel is a water bottle. I mean, I know I’m always going to be thirsty and I’ve discovered water fountains/ bubblers aren’t as ubiquitous in the rest of the world as they are in the US.
Unfortunately, carrying bottles can be a bit of a pain – especially since you often have to leave them empty during flights, causing them to compress and deform even more than usual under the cabin pressure (and that’s not helped by the fact that most disposable water bottles are made of that super flimsy plastic these days). Aluminum bottles definitely get around this – but there’s still the problem of the bottle taking up valuable luggage space when it’s not in active use.
For all of those reasons, I’ve come to love these Platypus Water Bottles. They are basically reusable water “pouches” that are completely flat when empty, bulge out like a regular bottle when full, and shrink in size as you drink from them. That’s handy because you’re not carrying around a bulkier bottle than necessary during the day, and when you fly, you can just roll it up or pack it flat in your bag. It’s really such a simple idea, but I guess some of the best ones are.