So I just ordered a new Kindle WiFi earlier this morning and I noticed that while Amazon doesn’t mention it on the Kindle product page, you can actually get $30 off the Kindle WiFi and new Kindle 3G by signing up for and using an Amazon credit card to make the purchase if you don’t already have an Amazon card, making the WiFi model just $109 and the 3G equipped model $159.
After you sign up for and get approved for the Amazon rewards card (it took me less than 5 minutes from start to finish), Amazon will deduct $30 off your first purchase (this offer applies to other products as well). So the order will show the regular price for the unit once confirmed, then the discount will appear as a credit on your credit card statement.
The good thing about the credit card is that you don’t have to continue using it, just order the Kindle with it and you don’t have to use it ever again and there’s no annual fee. Just be sure to pay the card off in full because the interest rate is its biggest fault in my opinion. The best rate you can currently get is over 13%, much higher if you have bad credit.