My Kindle ships in seven days, knock on wood, so this might be the last physical book I buy for a while. Turns out it was a cast-off from the Aurora Public Library. Aurora is not far from where I grew up. We went to the library a lot when I was a kid. Not the Aurora library, but one nearby.
I want to say serendipity because I like that word but I think this only rises to the level of happy chance. :)