The RPG industry seems to ever be moving to the digital world with PDFs duplicating and often replacing print books. Sometimes one may come across an beautiful gem among all the personal projects out there. I found some rules for Stephen King's Dark Tower series that look like they're for the Chaosium Basic Roleplaying System with some customized changes for the setting. These books detail the creatures and abilities found within. There is a very high production quality with these and as nice as they are, there is no mention or credit given to whoever created them. I suspect this may be because the creator didn't hold the license to legally make the books which shows what a labor of love these books truly are.
Here are the books in the series-