Both paper-printed and digital. I try to select a book each day pertaining to the current issues, and then I just open at random. I'd say about 75% of the time, I find a good quote on the first page.
I don't pick them in advance, so there's a deliberate attempt to find things pertaining to current events in terms of which book I choose, but after that, it's pretty much up to the gods of random pages.
A Peace to End all Peace was quite an eye-opener for me the first time I read it in about 2001, because I hadn't realized how involved the Ottoman Empire was in World War 1. That part wasn't taught in school! I highly recommend it.
That one gives the large-scale history; City of Oranges is a much more personal history of how the big-picture events impacted individuals and families. Also highly recommended.
There's actually another quote from A Peace to End All Peace that I'd like to use at a later date, if I remember to do so. I try to mix things up.
Maybe with what's going on with the House repukes, I might try to find something on the history of Ringling Brothers, Barnum and Bailey . . . .