on 07-06-2013 01:21 AM
If you are NookFriends with someone, you can exchange some ebooks through the LendMe feature. It's fairly limited in that not all ebooks are lendable, it's for a total of 14 days and is only good for one lend for the life of the eBook.
If you are close friends with someone, you can sideload B&N eBooks onto each other's devices. This requires you to unlock the book using the eBook owner's name and Credit Card information. Generally, you only have to enter the unlock information once on the device, but may occassionally run into a glitch.