Irminsul gets credit for this post. Predator is pretty much saying fuck you in copying Billy's laughter. The very last numeric symbol on the predators keypad is in fact a big middle finger! Fuck you Dutch!
Moke's shooting fall at the very end is very "fuck you"!! I'd do the very same as Moke Fuck you Stick! Fast forward to 2 min 30 seconds of YouTube if you only want to see the fuck you part.
It might not be a fuck you but...Gunnery Sergeant Hartman wasn't backing down nor gave a fuck about PVT. Pyle pointing the rifle at him. Its a fuck you to PVT. Pyle in my book!