The liquid metal gallium was used because it is a liquid at room temperature. Changing the voltage applied to it actually causes it to change shape. Varying the voltage enables it to become different shapes.
Besides being able to change form, it also has the ability to propel itself. When the metal was brought into contact with aluminum, it created hydrogen. This enabled it to move and powered it for about an hour.
Comment: You can be sure that governments all around the world will start to work on this discovery. Also, you can be sure that they will do it with the Terminator in mind. There will probably also be a number of commercial inventions coming out soon, too.
* * * * * * *
Source: http://news.yahoo.com/liquid-metal-discovery-paves-way-shape-shifting-robots-172747850.html
* * * * * * *
Graphics: Mine
* * * * * * *
Keywords: shape-shifting, metal, discovery, Terminator, China