FREE: $5 Amazon.com e-gift card

do you know if you can stack these gift codes? Like, if I get several together can I use them all at once? THanks

I'm not sure if you can stack them. I've never tried but since they are "Gift codes", I assume you can . . . :s Let me see what kind of research I can do.

http://askville.amazon.com/Amazon-allowed-gift-card-purchase-cards/AnswerViewer.do?requestId=57557591

~~Gift cards
Gift cards are redeemed to your account - use all of them to put into your account and either draw down as you go, or only redeem to your account an amount to cover your current purchase:

How do I use my gift card?

First, locate your claim code on the e-mail or paper gift card you received. If you have a plastic gift card, you may need to scratch off the covering on the back of the card to reveal the claim code (the claim code is not the same as the 16-digit card number).
If you're not ready to make a purchase: You can redeem the gift card to your account.
Go to Your Account.
Click "Apply a gift certificate/card to your account".
Sign in with your e-mail address and password.
Enter your claim code and click "Redeem now". Your funds will automatically be applied to your next order.

If you're placing an order through the Shopping Cart: Enter the code on the order form and click "Apply".
If you're placing an order with 1-Click: Click the "Review or edit your 1-Click orders" link that you'll see after clicking the Buy now with 1-Click button.
Then, enter the code in the Payment section on the next page.