I looked into Thingiverse as I have heard that it is a pretty big hub for the 3D printing community. I created an account and uploaded a project I am working on intermittently to design a Railking Husky Stack compatible shipping container. Right now it is just a rectangle with the right dimensions.
The site seems to work pretty well and even generated an image of what the project looks like so far (even if it is not much).
The site allows you to create your own collections which would be a huge benefit as you could name different collections depending on what they hold. For example, I put my shipping container in the "O Gauge Scenery" collection I created.
Here you can see what the collection inside looks like. Another benefit is that there is tracking among the accounts. So, if you posted something I could save it to my collection and it would still have your name attached to it, ensuring credit.
Dennis, you could still create your own system, but that seems like it might be a lot of unnecessary work when there are good out of the box solutions that are free. The only thing is that you likely have to spend time growing the collection. I still think it would be an extremely valuable resource.
Here is the link if you want to check it out for yourself: https://www.thingiverse.com/