One hidden place I found
 

Dunno if this has been mentioned, but there is a container next to the big crane you use to lift another container in the early part of docks area (Part 2 chapter 2 or 3 I think). To get to the container, you need to jump on the door of the crane controls, and from there on top of the crane and from there to the actual crane itself. Climb up a bit and you can leap to the open container that is otherwise inaccessible. It has buch of stuff that goes 'boom' to pick up...

Is this the 'last easter egg'?

Nope, 'twas mentioned.