profit center

noun

1. a segment of a business organization that has a profitable base independent of the business as a whole.
2. any source of profit.

Example Sentences

Bikes, thanks to Craigslist and eBay, are now easy profit centers for perps.

From Popular-Science

This happened because in the late 1980s the Brits realized that an airport could be an entirely new kind of profit center.

From The Daily Beast