He who remembers old grudges loses an eye, an Estonian proverb says. The cure for injuries is not to remember them is an Italian saying. But to remember is also essential and useful for humans. It is not for nothing that the storage of information, and materials and methods for it, have played a major role in our technological development, from the clay tablets of Mesopotamia to today’s DVDs and memory cards. The memories used for storing information are optical, magnetic or electric. But there are also materials that remember ... their own shape. Objects made of these materials can be deformed past recognition, and still resume their earlier shape...