For me it’s holding a VHS in the store and looking at the cover.
Big box computer games, with manuals and maps and those game brochures showing you all the other Ocean software products.
My brother collected these. I think he still has some of them somewhere. Like the original boxes for Diablo and Starcraft.
I collected some too, but I think I eventually got rid of mine. I was into the various Maxis Sim games, so I had tons of the boxes. SimCity, SimTower, SimPark, SimIsle…
The best manual was probably Ultima Online, an MMO. I read and studied the shit out of that thing. Used to bring it to school to learn all the spells and stuff. Also came with a good sized, folded-up map of the world on special paper.