I learned about an object-based (i.e. graph) DB twenty years ago. Blazing speed, but difficult to query. Fast forward to Neo4j and Cypher, and now I find it difficult to think of data structures as anything other than graphs!
I spent a lot of time in a large enterprise, and believe there are lots of opportunities to solve enterprise problems with graphs. If you are interested, or have ideas/projects, let me know. 