As an avid traveler, there are some things that I always carry with me on our travels, such as a camera, notebook, and either a roaming phone service or prepaid phone card when traveling overseas. Phone services have changed a lot in the past few years and it has become extremely simple to get connected to any part of the world, so why not stay connected with loved ones while you are away as well! It is the simplest thing in the world to carry some prepaid phone cards and use them from anywhere to anywhere, without worry about having the right currency, the right change or any such thing.
Now, when you search for prepaid phone cards on the Internet, you will get lots and lots of results, but be sure of where you actually buy it, since it's no fun getting stranded with a dud phone card, right? Sometimes, I find that it's really important to be able to get away from it all and like to go on vacation where there are no connections at all, just so I can switch off my phone for some time. It's such a relief not to be connected all the time.
Good luck on your travels!