Bought this jack-of-all-trades travel adapter in Heathrow a few years back. It accepts just about any standard plug you can think of and can plug in to just about any socket you are likely to find on your travels.
I always had doubts about its safety. Pins were exposed when plugged in and the female socket side of thing looked like you could shove things in to the live and neutral holes without too much trouble.
My fears were, partially, confirmed by this teardown.
