As cool as the X-Wing fighters were in the Star Wars films, the Empire's vehicle of choice, the T.I.E. Fighter, was the ship I loved the most. T.I.E. stands for "Twin Ion Engine". Today, there are several spacecraft that use an ion engine, including the European Space Agency's [[xref:http://www.esa.int/esaMI/SMART-1/SEMLB6XO4HD_0.html|SMART-1]]. This craft is a solar orbitor and the ion engine uses charged ions in order to generate thrust.