I am something of a literalist when it comes to covers. My covers are typically reflective of a broad view of the subject matter. For example, "Salvaging Capitalism/Saving Democracy" featured a green North America being sucked into a whirlpool, while a humanoid character is extracting Money before the whole continent sinks. I put this together as a composite of stock images.

The Corporation, being dystopian and about GMO food and pharmaceuticals has a rather stark and disturbing picture of a woman in white dress standing in the middle of a sun-burned field of grain.

My two most recent novels, somewhat lighter in tone, have front and back covers that again are photos the are reflective of the events in the story - "Trails" showing contrails (or chemtrails?) in the evening sky on the front and typical Arizona scenery on the back. These were my own photos. The sequel, "Fireballs" uses an NOAA photo of the Kitt Peak Observatory close to Tuscon (modified in PhotoShop to include a fireball, and a Delta 4 rocket, courtesy of JPL/NASA on the back - again consistent with the plot.

"Great Expectations" - Dicken's lays bare the struggles and the hypocrisy of England during the Industrial upheavals. His plot twists and character portrayals are magnificent.
"Huckleberry Finn" - any book that has been banned something like five times for wildly opposing reasons has to be considered a classic. Like Dicken's, Mark Twain understood and portrayed the struggles of those who live in an unfair society.
"Confessions of an Economic Hit Man". No novel this, but a glimpse behind the curtain in a shadowy world of exploitation, Perkin's work should be on every thinking person's list.
"Poisonwood Bible" and "The Lacuna", both by Barbara Kingsolver, are eyeopening fiction based on factual events.
Now for the next hundred or so favorites ....

Cluttered. I'm a bit like the "professor", Cosmo Fishhawk in the cartoon "Shoe". If I try to un-clutter my desk it just clutters my mind.

I grew up in Eastern Canada, on the coast, so have something of an affinity for things nautical. But the biggest influence was probably the fact our Junior High School (gr 7-8) was across the street from the public library - and our principal arranged adult borrowing privileges. These two combined, in grade 8 I read the entire Bounty Trilogy. Later I read nearly every novel written by James Michener, and most written by Lean Uris.

Fireballs was in part inspired by the explosion over Chelyabinsk, Russia, in February of 2013. A documentary film on that was the trigger for the story, but of course the local and detail, and the major themes, came from other contemporary or past events.