Castles & Crusades by Troll Lord Games has been around for quite some time now. It was first released in 2004 as a simplified version of WotC’s d20 System inspired by old-school D&D. If you always wanted to check out the game now’s your chance! Troll Lord Games is giving away both the Players Handbook as well as the Monsters & Treasures book for free (in digital form of course) on their official store. In addition to that the adventure “Rising Knight” is also available for free from DrivethruRPG. As far as I understand these offers end on January 2nd, so you should act quick.
Michael Wolf is a German games designer and enthusiast best known for his English language role-playing games blog, Stargazer's World, and for creating the free rules-light medieval fantasy adventure game Warrior, Rogue & Mage. He has also worked as an English translator on the German-language Dungeonslayers role-playing game and was part of its editorial team. In addition to his work on Warrior, Rogue & Mage and Dungeonslayers, he has created several self-published games and also performed layout services and published other independent role-playing games such as A Wanderer's Romance, Badass, and the Wyrm System derivative Resolute, Adventurer & Genius, all released through his imprint Stargazer Games. Professionally, he works as a video technician and information technologies specialist. Stargazer's World was started by Michael in August 2008.