Amazon is offering a $5 credit when you connect your Amazon and Twitter accounts and Tweet their special message. You will need to go here to link your accounts and follow the directions.
Fine Print: Although the price shown on the “Buy” or “Rent” button will not change, your credit will automatically be applied to your purchase. After your purchase, you can confirm that the credit was applied by checking your order confirmation, which will be sent to you by e-mail. To receive this offer, you must click the button above to follow Amazon Instant Video and Amazon Movies & TV on Twitter and tweet the above message between August 29 at 2011, at 10:00 AM PST and September 2, 2011, at 11:59 PM PST. Offer limited to one promotional credit per Amazon.com customer.
(Thanks Addicted to Savings!)