$50 Amazon gift cards are just $40 at Meijer (in store only, with coupon) through July 4th.
It's part of Meijer's "Summer Bucks" promotion which can be used on any general merchandise purchases including Amazon Kindle gift cards, PSN cards, video games, etc. The amount taken off per purchase varies. In this case, it's $10 off anything over $49.97.
Note: The promotion will not work on regular Amazon gift cards - only Kindle cards, which can be used to purchase anything on Amazon.
Just sign up for mPerks (Meijer's digital coupon website), clip the "Summer Bucks" coupon, go to your local Meijer store, grab an Amazon Kindle gift card (in the electronics section), and head to the checkout (use the self-checkout...it's way easier).
You can only use one coupon per transaction - however, you can repeat it as many times as you'd like. I bought 8 $50 Kindle cards for $40 each on 8 different transactions, then cashed them in on my Amazon account for my PS4 preorder, which makes my PS4 $320 out of pocket instead of $400.
Not too shabby.
I've been taking advantage of this for a few years purchasing $50 PSN cards for $40, but didn't think of trying it on Kindle cards until now. But I'm glad I did!
Meijer Store Locator (locations in Michigan, Indiana, Illinois, Ohio & Kentucky)
Meijer mPerks website (sign up, sign in & clip coupons)