Amazon.com offers a $10 Amazon Credit when you add $20 or More to your Amazon Balance using Amazon Cash. Works with CC at CVS also.
Note, this is a limited time offer, one per Amazon customer account. Promotional credit expires at 11:59 p.m. (PT) August, 31, 2017. Offer only applies to products sold by Amazon.com. For additional details about Amazon Cash, see the page here, the Amazon Cash FAQ and the Promotion Page for complete terms and conditions.