Well, this process seems a bit counterintuitive, eh? This morning, Barnes & Noble introduced a new scheme for getting Nook customers to visit the company's retail stores. The promotion nets you one free e-book when you purchase another, but -- and this is where the offer tripped us up a bit -- you can only make your electronic purchase with a cashier in a physical store. The deal will be up for grabs every weekend, and titles are set to change. There are currently 20 books on offer (available this Saturday and Sunday only), including hits like Along Came a Spider by James Patterson and Bossypants by Tina Fey. Once you make your selections, you'll receive an email with access codes (assuming the rep managed to input your data correctly), at which point you'll need to visit a dedicated Barnes & Noble site to receive your books. Easy peasy.