Wide grip pull ups, pendlay rows, deadlifts (only when back day falls on a weekend), seated row (close and wide grip handles), face pulls, shrugs, lat/rear delt dumbbell flies, and other random shit. I don't do ALL these in the same session, usually try to alternate between some of them every other session. Most exercises are supersets too.
I put more effort into my back sessions than chest sessions, mostly due to rarely deadlifting lately.