Americans and Canadians who have a library card: if your local library is associated with Hoopla, you can use your email address and library card number to borrow materials electronically via their web site or app. I see about half our book club selections available as either ebook or audio book selections there. They also have a selection of comics, movies, music and TV shows available for borrowing. The number of downloads you get per month is controlled by your particular library, so if you want more, complain to them
. Tech: you can view all Hoopla-borrowed items on Windows/Mac, and there are apps for iThings and for Android. Bonus: on Android, at least, Hoopla's app can pipe your borrowed media to a Chromecast.Also, for people in every country: a lot of books out of US copyright (almost always the longest) can be found for free download to your reader of choice at Project Gutenberg.
If you know of other good free and legal book sources (let's not get Jacob into copyright/DMCA trouble) please be so kind as to link to them below.