Since I don't get my membership discount on ebooks, I'm always looking for other ways to save money on my purchases. This means one of two ways: watching for ebooks to come on sale, or getting deals on gift cards.
Occasionally Barnes & Noble will offer a deal on gift cards. They have one now, but it'll only be good until June 6th: If you buy $100 worth of gift cards (doesn't have to be one $100 gift card, can be several with amounts that add up to $100) they'll give you an additional $10 gift card. If you buy the $100 in gift cards for yourself, that's basically like earning a 10 percent discount on ebooks... But if you're planning on getting someone a gift card anyway (say, for a Father's Day present) you could be getting even more of a discount!
Just click on the ad in this blog post. If you click on it before midnight (East Coast time) on the 6th, you should see the offer for a free $10 eGift card at the top of the page in blue.