In one (I can't find the title), MIT students make an SGAI and somehow manage to keep it contained (away from the internet). They feed it animated Disney movies and it cranks out the best animated movies ever made. They make billions. Eventually they make "live-action" movies that are indistinguishable from the real thing. Then they make music, books, etc, and create an unstoppable media force.
They could leverage the AI to discover hyper-efficient supply chain methods.
They could sequence genomes and run experiments, and sell the data.
Possibly exciting things around weather prediction.
Very exciting things around any research.