Bundle of Holding is offering a new bundle featuring a really huge amount of support for Dungeon World. Among the list of PDFs is my own Iron Edda: World of Metal and Bone, published by Exploding Rogue Studios. In addition, you also get the original Dungeon World rules, a few adventures, and if you pay above the bonus level, some interesting settings like Inverse World and The Last Days of Anglekite. You can pay what you want (minimum $6.95), and a portion of the proceeds goes to support Doctors Without Borders.
World of Metal and Bone is a complete RPG based on but diverging from Dungeon World in a lot of ways. If you pick it up with this Bundle, you'll have an entire game of epic Norse fantasy waiting to hit your table.