Adobe
At Adobe I've worked on two teams that facilitate collaboration with Creative Cloud Libraries. The first is a standard web application, and the second is an Electron-like app that's embedded into products like Photoshop and Illustrator.
One feature I worked on is called public links where users can create shareable links to their libraries. Others can follow or copy the library and use the building blocks to create new designs. For example, here is the Google Material Design style guide as a CC Library public link.
