The king of publicity is product placement – showing your product in movies, or other entertainment media. TMZ showing a big celeb wearing your hat can make you rich.
But mostly it takes a lot of money to make that happen. Reeses Pieces in the movie ET cost $1 million.
Also, do you think that is a new idea? Think again. It goes back to silent movies.

A Brief History of Conspicuous Product Placement in Movies.