Answer by Andrew Corradini, CEO, 'green' stuff, energy, fuels, on Quora.

  • A Towel. Now for serious stuff:
  • Plastic Grocery Bags. Even better than a towel. Handy for: dirty clothes, anything wet, anything that might leak, buying stuff at markets, many other uses. And: they take up ZERO room, so why-the-heck-not bring a few? Ditto plastic ziplock baggies - bring 3-5.
  • Clear Plastic Document Sleeve(s). The kind that's open at top and side, preferably brightly colored. Put this in your carry-on right next to your laptop (keeps it from creasing/crumpling and makes it easy to find fast), or in the outer pocket. Put your boarding-pass printout*, itinerary, car-rental printout, and hotel reservation in it. When you get your luggage check tags, put those in it; ditto gate-check tags. (And if you're the type to rip articles out of mags on the plane, or save things as you travel, it's perfect for those so they don't get crumpled. They're great for receipts, too.) My brilliant and well-traveled wife taught me this one - it'll change your life.*NEVER rely on your cell phone boarding pass - ALWAYS have a hard-copy backup. If you're rushing to the gate and your cell is dead - the two possible related consequences of a delay, like traffic - you'll be really happy to have the dead-tree copy.
  • Food Poisoning Meds. Imodium, Cipro, Pepto, whatever. Assume you're going to get it. Being on an over-water flight with major cramps and every-15-minutes lav runs (ahem), and no remedies, is hell itself. And this isn't just 3rd world; apparently most people in China, even in big cities, expect mild food poisoning once a month or so.
  • Medical Alert Info in Local Language(s), if applicable. If you're allergic to bees, have a bleeding condition, etc., a med-alert bracelet in English, with no instructions, might not be enough info for locals. Similarly, an "in case of emergency call: ___" wallet card isn't a bad idea.
  • Emergency Cash. Both US and local. Get some local the second you land, from an ATM (Thomas Cook exchange stands are ripoffs and avoided by all seasoned travelers). Know the appropriate exchange rates (and preferably get a card that doesn't charge conversion fees - tough to find but worth it). You might have a helluva time finding a place to get local money without extortionate rates - plan ahead. And: the US$ is often better than gold bars, in some places, although in many of those places you might want to keep it in your shoe.
  • "Outboard" Battery with USB. You have no idea how long you might be in traffic, or away from a hotel plug with an adapter, and your smartphone might have critical data, your language dictionary, or access to something you need desperately. Or you might need to call, for example, the airline (and be on hold forever!) to move a flight. Or the police or embassy. Having a 2500ah charge (preferably way more) could mean a huge difference in an 'unexpected' situation.
  • Extra Laptop Battery (optional). Ditto. You can't count on power on planes, or somewhere else, and you never know where you might suddenly really, really need your laptop. Batteries don't weigh that much...when you need 'em.
  • Entertainment. Nothing worse (after food poisoning) than being trapped on a tube for hours realizing the plane's flicks are on a small screen right next to your row and mostly consist of reruns of "The Big Bang Theory" and the latest Jennifer Aniston rom-com. And the in-flight magazine featuring what you should do in Alberta with Brad Pitt. And your seatmate loves to talk about mixed martial arts. (And your laptop battery died - cf. above - and you're sick of work anyhow and that's all you had on it). Bring movies, and a Kindle (with reading light!) loaded with books. I will not digress on the 7-8 authors, 2 of them dead, available at airport bookstores.
  • Phrase Dictionary. On your smartphone. Preferably one that talks for you, or at least has the words/characters onscreen, especially if the language is non-European (even more especially if it's Asian and uses characters).
  • Laundry Detergent Packets. Ever run out of clean underwear and had to hunt down a store and buy more? Spilled something on your last clean shirt/blouse? Washed in the sink with the hotel shampoo/shower gel? They make 1-shot packets of Tide and Woolite; they're hard to find, so when you do, buy dozens.
  • Eyeshade and Earplugs. You might want 'em, you might not be given 'em, and they take NO room.
  • Dopp/Travel Kit Items: (with you, not checked!): Rx's, ibuprofen, sewing kit, band-aids, moleskin/heel patches, triple-antibiotic ointment packet, dental floss (has many uses!), very small scissors,
  • Multi-tool or Swiss-Army-Knife (checked): with knife, corkscrew, screwdriver (both types), pliers, etc. They make small ones. You'd be surprised how often you'll be glad you have it.
  • Flat Water Bottle. Again, zero space required, so why not? Get water at the airport past security or at your hotel and stop buying bottled.
  • Sharpie. Can't say why exactly, but you'll be surprised at how often it comes in handy. Ditto a hi-lighter.
  • Sunscreen. Like the Baz Luhrman song. Get a wee bottle, or even packets. By now you should know I'm a huge fan of one-use packets.
  • Dropbox Backup Documents: copies of your passport, itinerary (with confirmation codes!) and tickets, medical insurance card, birth certificate (and your kids if you're traveling with them), umbrella liability policy if you have one, emergency contacts (including maybe embassies), and online account numbers (like airline/hotel FF#s). I don't recommend passwords unless you're using good security on Dropbox itself - you should be using Lastpass or 1Password anyhow.)
  • Online Security Precautions - 'Disposable Laptop' (and phone): If you visit China or South Korea, probably Russia, and other countries, you can assume your computer will be hacked within moments of turning on WiFi or connecting to the internet. Count on it. Do not store passwords or sensitive company data on it. When you get home, it will probably still be infected and continue to communicate with the mothership. You can assume your firewall, AV, and anti-malware will not prevent this. If you work for a big company, talk to IT first about this. If you don't, you may want to find an old laptop to take with you, and wipe it when you get back. If you think this is paranoid, Google it. By the way, if you're an executive of any company of significance, and/or you're staying in the major hotels in major cities: your room is quite possibly bugged. I am not making this up.
  • Online Access: Some countries filter the Internet massively, which turns out to be more of a pain in the ass than you'd think. A good VPN can help you here. (I like VyprVPN a lot - a commercial product I have no relationship with - it got me past the government firewalls in Syria, Turkey, and even China.)
  • Exchange-Rate Wallet Card. You have to make/print this yourself. But: it is so handy to have a credit-card-sized thing with a column of dollars to local money, from $1 to $1,000 in increments, on one side, and the other way on the other side - you'll be amazed you ever got by without it. (For extra points, laminate it. You can buy little sleeves at any Staples/Office Max-pot.) Trust me.

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