If you're Sir Terry Pratchett and you want a sword — as a good knight should — you can't possibly go about it in a typical fashion. That just wouldn't do. So instead of looking for something expected like steel, Pratchett decided to draw inspiration from the skies and make a sword with a meteorite. From the News.com.au report:
Well, it does stand to reason that a knight would need a sword, doesn't it? But, as the article indicates, the sword now poses a bit of a problem and Pratchett has placed it somewhere secret. Somewhere safe. According to the author: "It annoys me that knights aren’t allowed to carry their swords. That would be knife crime."
(via BoingBoing)