This deal requires a tiny bit of work, but in the end will give you a relatively easy way to get roughly 25% off any Kindle (immediately). You get the most bang for your buck with the purchase of a Voyage and Oasis, but it works with the purchase any currently sold Kindle.
1) Search on eBay for a broken or cracked-screen
Kindle e-reader (any generation). They are almost always available for around $10-12 shipped. The only thing you need to watch for is to make sure that it will be delivered within one week.
2) Go to the Kindle Trade-In page [amazon.com]
and set up a trade-in of the model that you purchased. For models that are not functioning or have cracked screens, you will get a trade-in value of $5.
3) Choose the Instant Payment option to immediately get the $5 gift card and a 25% off coupon for ANY Kindle e-reader applied to your account.
4) When your eBay Kindle shows up, print out the trade-in return label, tape it on the package, and get it in the mail within 7 days.