There is an interesting interview with the producer of Babylon 5 where in theory he is owed 10's of millions because he traded salary for a large slice of whatever profit showed up.

However, the contract was written so they could do some accounting tricks and make it look like the show was a net loss. He knows the game well enough to know he was never going to see the money. But there was an odd moment where an executive happened to mention the actual billion in profit from the show. And he said something about his cut. At which point the executive said something about how it was still in the red. Even though as a producer he know how much the show cost, he could read the subtext and in the interview he said "I want to keep working in Hollywood and I know the game."

However, if he took them to court he could probably get a large payout at the cost of never working in Hollywood again.