And I'm giving it away for free. Why? Because you'd need 500 million dollars to fund it, that's why.
It'd be a chain of stores that sold DVDs, like Suncoast; however, when you went in, there wouldn't be any physical DVDs. Instead, there'd be catalogs/displays/empty cases to browse through, filled with listings of movies and TV shows. When you knew what you wanted, you'd walk up to the counter, and tell the salesperson...
And they would connect to a (highly secure) server on a high-speed line, burn the DVD for you, print out a sleeve and slip it into a jewel case, and you would walk out with it.
Think about the huge advantages. No DVD would ever be out of print. Inventory management would be just a question of, "How many blank discs do we need to stock?" You could continue to reap profits on films that have been out for ages, because you wouldn't have to estimate demand. It's got all the bonuses of Print On Demand for the book industry, only it's quicker, easier, and it's what the public is already practically doing. Plus, you could allow people to select and add as many special features as they want ("that comes with the commentary track, would you like to add on a theatrical trailer and 'making of featurette'?") You'd have a lower overhead, and thus would be able to sell DVDs cheaper than any other chain in the industry.
Of course, there are issues. One, the "highly secure server". You'd need to make sure it was very, very, very highly secure. Securing the server and keeping it secure would, in fact, be your highest ongoing business expense. Two (and two is the reason I'm giving the idea away), you'd have to get at least one major studio to sell you the rights to its film library for use in this fashion (or lease, hire, rent, or whatever agreement you'd care to come to), and probably several if you wanted to have the kind of selection you'd need to have to compete with Suncoast and Best Buy. And the money you'd need to do that...well, I'd estimate nine figure sums, and probably a percentage of the profits as well.
But once you got the astronomical start-up costs out of the way, wow, would it be a money-maker.