My favorite exercise is something I've never seen done by anyone. Maybe I even invented it...probably not though.
You put yourself in a seated chest press machine. Then, you turn your body to the side against the chair, so your upper lat and side delt are resting against the seat. Then, you grasp the handle that you're facing (your back should be facing the other handle). Then, one arm at a time, you press the handle you're facing.
The handle's trajectory is across your chest, instead of away from your chest.
It's not like I've invented a magic angle or plane of movement...it's just new to me. When I do it, I get an insane contraction and pump, it's easy on my rotator cuffs, and it allows for a great stretch and squeeze.
Anyways, if you can decipher what I'm trying to explain, give it a shot. It's not a "heavy weight at all costs" exercise. It's a groove movement. Some of us older guys have to groove our lifts for the pump and burn nowadays...this one works nicely for me.
Another movement I like (I like unilateral work, by the way):
You go to a standing cable apparatus, and put the single handle on it. Grasp the handle, and turn away from the machine (face away from the stack). Then, step away from the apparatus so you can feel the stretch, and simply press the handle down and away (the closest approximation would be a 1-arm decline dumbell press type of groove). I like it because of the constant tension, I don't have to get myself into a ridiculous decline bench (if your gym even has one), it's easy on the shoulders, you get a great contraction, and there's a bit of ab work in there too as you brace your upper body against the weight stack pulling you back. Give it a shot if you're bored.
I can't believe I just posted training advice on getbig.