You can now buy power adapters from Amazon (and I presume other retailers) that can be...adapted... so they can fit into any socket into most regions of the world, and also adjusts to what you are plugging into it. You can even plug in multiple USB cables for ipads, cameras and phones etc into them, so you only ever need 1.
They are inexpensive and vary in colour and should last for a long time... as long as you don't plug in something like a shaver, hairdryer or kettle into them.
No i'm not a salesperson!, but I consider this an essential for when I travel now.
Chris