Amazon has a new trade in program. I don't know how long they've been running it, but it just crossed my desk today. Sign up for the program and Amazon will give you an immediate $20 discount on your next Kindle, and what's more they will also give you a gift card when you trade in your old ereader.
Yes, Amazon is offering 2 discounts here, not one. The offer is good if you want to buy the basic Kindle or the Kindle Paperwhite (but not the Kindle Fire tablets), and the trade in offer is only good on a limited number of older models.
The trade in values are as unimpressive as Amazon's other trade in programs for book and electronics, with Amazon only offering $15 for their competitor's hardware. But if you choose to part with an old Kindle Paperwhite you could get up to $68.