‘Shape memory alloys’ (SMAs) are an extraordinary material. Just like an elastic band they can be stretched and deformed and will return to their original shape at a given pre-programmed temperature. ESA developed SMAs for use as lightweight temperature-controlled actuators in space. The Italian company Grado Zero Espace is now using SMAs in a shirt that ‘irons itself’ at body temperature. This shirt has been awarded the ‘Best Innovation of 2001’ award by Time Magazine. Another possible design is a shirt with sleeves programmed to shorten as the temperature becomes hotter.