Blood Meridian by Cormac McCarthy. The prose is beautiful and mesmerizing. It forces me to read it at the speed of speech, to let it flow. I'm a sucker for long and winding sentences (when they're done well), and this doesn't disappoint.
It's also quite disgusting, just as everyone says about it. If you can't handle brutal senseless violence, don't pick this up. It's pretty interesting to see the racism/xenophobia of today reflected in American history (1850-ish). It reminds me of the Dark Forest theory from Three Body Problem: these guys go around killing not just out of a love of violence, but because it's the only guaranteed way to come out on top. If you aren't the killer, someone else will be. Capitalism and greed work like this too.