All the Light We Cannot See by Anthony Doerr
I've been on the reserve list for this e-book at the library for a long time. When I received notification that it was finally available, I had just started another book, was about to leave for my quilting retreat, and I had a ton of things to get done around the house, so I was almost entirely through my two week check-out period before I started reading it. I'm about a third of the way through, and my library loan is about to expire. Luckily I know a little work around for keeping library e-books past the due date with nary a smidgen of guilt.
I think I've posted this tip before, but it bears repeating.
I keep my old Kindle e-reader solely to read books on. I like to read on it because it is much lighter weight than my Kindle Fire, but also because when I have a library e-book on it, and it is close to the due date, I just turn the wifi connection to my e-reader off. That way the library recalls their e-book from my Kindle account so it's not overdue, and the next person on the wait list can have it to read. But since my device is not communicating with Amazon via wifi, the book stays available to read on my e-reader until I turn wifi back on to the device (which hopefully I remember not to do until I finish reading the book). No guilt, no fines, no muss, no fuss. So awesome.