This is a tip from a Corporate Traveler.

Use one credit card when you are on your trip specially to a foreign country. As soon as you get back to the United States, give the credit card company a call and let them know that you lost your card and need another one even though you have the card in your possession. Make sure they deactivate your old card and send you a new one. This will reduce the chances that someone can use the number on your card in the near future. Most of the eastern European countries are notorious for fraud and credit card abuse. I use the credit card because it still has the best foreign exchange rate. Plus, I don't like to carry large amount of cash with me.

Scan all the Passports, Drivers License, Credit Cards, and Emergency Phone Numbers and keep it on a USB thumb drive that you will always have with you. If your passport gets lost during international travel, it is a major pain to get another one. If your wallet gets lost, then you at least have a copy of the card information which you can cancel. Keep the thumbdrive always with you like your pocket.

Create a GMAIL account and email the scanned passport, credit card info, etc.. to your new GMAIL account. In order to protect yourself from someone taking your documents by email, there are programs that can encrypt the content of the email.This is specially helpful just in case you lose your passport and at least you can access GMAIL anywhere in the world and access your account and your documents.

Print out a copy of all the scanned documents mentioned above and give it to 2 people in the United States. You can also leave them a CD with the documents. If you are not comfortable emailing the documents to a GMAIL account that you can access anywhere in the world, then this is another option. Just in case you lose your paperwork/passport, you can call someone and have them fax or email to you.