For those of us that love to read and somedays can do nothing else, there is a website www.bookbub.com. Everyday you are sent free and radically discounted book options that can be downloaded to your e-reader. I think I have spent about $4 and have over 300 books. What a find. It is certainly worth a look.
Also, on Amazon there is a section (you will need to look for it) that lists over 100 free books that aren't part of the library collection.
This, plus ordering back issues of puzzle books has kept my mind from atrophying (I think).