In anticipation of my third and last move this year, I was doing some thinking about my worldly possessions. I came to the conclusion that I own and love many vessels: bottles, flasks, beakers, boxes (wooden, metal, and paper), cups, satchels, etc. that serve no purpose other than to contain other objects and substances. Unfortunately none yet of the oceangoing variety.
I had a similar realization a few summers ago, when I had a job organizing the toolchests of the Yale recording studio: the majority of them were filled with things that served as attachments, that is, something you can use to attach one thing to another. Recording engineers are obsessed with finding clever and elegant ways to do this. The primary situation is mounting microphones, which sounds simple until you ask a recording engineer to do it.
Objects are more meaningful when we can sort and group them, and use them in conjunction with each other.