Potter a boon for ... HarperCollins?(Chamber of Revenue)

Forget Jo Rowling, there's a far more unlikely player who can make out deposit slips now that Harry Potter has raked in the sales: HarperCollins.

The book's success has had many beneficiaries, from UPS to Running Press, whose impulse-buys saw a spike. But in a little-known deal, Harper has been handling all billing for Scholastic since 2001.

The deal means revenue of as much as $8 million or $9 million for the new book. Sources say Harper gets a single-digit percentage of Scholastic's revenue for a book, which for Half-Blood could be $200 million. HC COO Glenn D'Agnes declined to comment on revenue.

Unlike traditional fulfillment deals, the house …