Mostly things that are to stay in space, or can't be launched assembled.

The ISS was built after lots of launches of components, they can also build small satellites or other things that stay in space.

That's the current use. But in the far future, space ships or habitats probably. Things that can't hold together under the weight of gravity or areodynamic drag. Like tyco station in the expanse.

Thanks. I was imagining something that would be made in space, then shipped back to earth... and thinking there is nothing that would be worth the shipping costs, except something small and (perceived to be) high-value, like synthetic diamonds. I could see someone spending $$$$ on an engagement ring made in space just so they can say it was made in space.

That seems to be the case now; perhaps if large scale operations of reusable vehicles make shipping costs decrease significantly then the economics of that would change.

I think the current ISS is hosting an experiment at making ultra-high-purity optical cables.

I think fiberoptics is one thing that benefits from microgravity.