Dallas. The 'lightsaber' used by Darth Vader, the villain of the popular film series 'Star Wars', was sold for more than 4.87 million US dollars at an auction house in Dallas, America on Thursday. Vader used this weapon before uttering the famous dialogue 'I am your father'.This item, described by Heritage Auctions as the character's 'principal conflict lightsaber', has become the most expensive memorabilia ever sold at auction in the history of 'Star Wars'. This item was used by actor David Prowse and his stunt double and Olympic fencer Bob Anderson in various combat scenes.This weapon gained the most attention...