I’m old enough to remember when travelling was mostly a massive exercise is personal security. I blame American Express, mainly, and their chillingly effective commercials depicting young honeymooners tearfully calling their parents after her purse had been artfully lifted from the back of a chair in an outdoor café, or befuddled senior citizens asking “what WILL we do?”

So naturally packing meant a solidly uncomfortable and, really, totally impractical money-belt with your traveler’s checks and tickets and passports and reservations and traveling meant stripping down and exposing your valuables whenever you went through security or boarded a train or had to pay for something.

ATM cards and just general experience have eliminated the stranglehold the evil geniuses at American Express held on the imagination and the traveler’s check is, thankfully, a thing of the past. Indeed, unless you’re making off with the proceeds of a jewel heist, there’s no reason to have a money-belt anymore at all. Whatever you might have been tempted to put in one has been replaced by the cloud:

ATMs and the Euro are the new currency traders

I still see those dead-eyed money changers at airports and train stations and I wonder who’s left to prey on. Who can still make it to an international airport with nothing but a wad of cash and no way to access their bank account in local currency? In fact no one, as far as I can tell, and by and large their tellers appear to be reduced to the role of ad-hoc information booth.
So don’t ever change your money. The trick is this; whenever you leave somewhere for a destination that uses a different currency than where you are are, be completely out of money. Take cash out of the ATM in small, safe amounts that you can afford to lose and you’re certain to spend or can donate to the World Wildlife Fund at your departure gate.
Incidentally the currency traders still have a revenue stream in their own ATMs. If it need be said, do not use them. Any ATM is going to charge you to access your own damn money but for the currency traders this is all they’ve got left and they can’t let go of the glory days when they had you at their mercy.

The cloud is the new tearful call home

Before you go, scan or photograph your passports, credit cards (just the front, if you’re concerned about hacking) and all your tickets and reservations and either email them to yourself or, even better, upload them to Google Drive or Microsoft Skydrive where you can access them from any computer with an internet connection (ie, any computer). By all means have printouts of whatever tickets or reservations are more convenient as hard-copies but above all know that nothing bad is going to happen. You can lose pretty much everything and so long as you can get online and to your bank or embassy you can get it all back again in 24 hours. The real objective here is not to travel physically lighter but psychically lighter.

E-Tickets are the new tickets-tickets

Just about all western travel can be done these days without issued reservations. There remain some archaic peculiarities, such as the very German train ticketing system in which a ticket entitles you, in practice, to buy a seat. But even these amusing cultural curiosities can be accommodated online and you can almost always select some variation of print-at-home.
I remember when I first encountered print-at-home tickets and being utterly perplexed: what was to prevent me from printing all the tickets I wanted and inviting my friends for unlimited free travel? Of course, apart from the fact that each ticket has a unique and irreproducible code and a scannable motif — usually a QR code — I just wouldn’t do that and neither would most people. This is the evolution in thinking that facilitated e-tickets — the realization that the comfort and convenience of the vast majority of passengers was a more important objective than catching the few cheats.
Refer above to the cloud. By all means print your tickets but don’t have a regularly-scheduled freak-out when you forget where you put them because it doesn’t matter any more — you can print them again or, as often as not, just show the conductor the confirmation on your phone.
Airline e-ticketing tends be even more convenient these days and self check in should be nominated for some sort of Nobel prize. Typically you arrive at the airport (as usual, way, way earlier than you should need to — security theatre has only gotten worse) and scan your passport through a machine which offers you seat selection and prints out your boarding pass. Self check in is such a sea change from the rote torture that, really, wasn’t that long ago that it can seem a little suspicious at first but it’s actually as simple and convenient as it seems.

Carrying a little less paper isn’t going to make your luggage much lighter but that’s always a secondary objective to enjoying where you are and the time spent getting there. So take a little weight off your mind, put it in the cloud, and it’ll follow you wherever you go.