Overstock.com has announced that members of their loyalty program, Club O, will now receive "Club O Dollars" equaling 15% of a book purchase price to use toward future purchases. The announcement follows the company's price war with Amazon in late July when Overstock priced 360,000 book titles 10% below Amazon's prices.

"Last month we started a book pricing war with Amazon," said Overstock.com chairman and CEO Patrick Byrne. "We're hoping to continue that battle, in a way that lessens any harm to the mom-and-pop booksellers we consider our comrades in arms."

According to Byrne, the offering undercuts Amazon's book prices for Overstock.com's most loyal customers, without adding undue pricing pressure on independent bookstores. Club O memberships are available to Overstock.com customers for $19.95 per year.