Barnes & Noble is offering a new free e-book every week for the next few weeks, with a twist: to redeem the e-book download, you have to come into a Barnes & Noble store and show them your Nook or your general-purpose device (iPad, iPhone, iPod Touch, Blackberry, HTC HD2, PC, or Mac) running Barnes & Noble’s eReader. (Or just bring the device and the staff will help you put eReader on it.) You then receive a voucher you can redeem at B&N’s website to download your e-book.

On the one hand, this seems to negate one of the key advantages of e-books—the ability to get them without having to bestir yourself from your comfortable chair. But on the other, it is a way to get people into the store, at which point they might theoretically buy a physical book. Though on the gripping hand, it is doubtful too many people who want a free e-book will be terribly interested in buying a costly physical one.

This week’s free title, available through May 23rd, is The No.1 Ladies’ Detective Agency by Alexander McCall Smith. Next week’s title is Storm Front, the first Dresden Files novel, by Jim Butcher. Other titles will include The Long Tail by Chris Anderson, Home Safe by Elizabeth Berg, and One Shot by Lee Childs. All e-book vouchers can be redeemed through July 1.

More information can be found in Barnes & Noble’s press release.

(Found via Nate’s E-book News.)