Below are screenshots from a proof of concept product called "Bitcoin Checkout". The product would allow users to purchase items from amazon.com with bitcoins.
The primary goal for this project was easy of use. It was designed so that user accounts aren't required to get started or place an order.
Users would input a product URL into the textbox on the homepage or the cart page and click "Add to Cart". Then the product would perform a query to Amazon's Advertising API in order to get product information such as the name, price and a picture of the item. At that point the item would be added to the user's shopping cart. The estimated cost in bitcoins (in this case mBTC, or 1/1000th of a bitcoin) is displayed and updated periodically. Once the user has selected all of the items they wish to purchase they may checkout. The checkout process asks for shipping information and then once the user confirms their order they are given a Bitcoin address to pay for the order balance. Payments are processed using the Coinbase API.