Hi! That's a good question 
We don't have any official case studies (yet!) but the projects tag on the forum has some Prodigy-related projects, papers and blog posts by others: Topics tagged project
Some users have also contributed their custom recipe scripts to the prodigy-recipes repo. If you have a specific industry-use case, you can also browse the forum tags like "medical", "HR", "legal" etc., but this is going to be more related to specific workflows and annotation strategies people are building, so it might be very specific. But here's a nice example for a medical use case for instance, complete with a paper:
(One thing that makes detailed case studies a bit tricky is that because Prodigy is very data-privacy-friendly, many of our users are working with company-internal or otherwise sensitive data that they can't really share or talk about much. And since training and annotation is mostly about data, it can make it difficult to show full end-to-end case studies. But we're currently working on ideas for this!)