If you read books using the Kindle software for Windows or have a physical Kindle device and you happen to be running the Windows 8 Consumer Preview then you may want to search the Windows Store for Kindle.
Earlier today Amazon released their preview Kindle Metro App for users of the Windows 8 Consumer Preview.
I found it interesting that they used the term Cloud to show what books you own that are stored by Amazon – I am not sure I have seen them use Cloud like that before.
If you have never used a Kindle or the software for Windows you can still try this out by logging into your Amazon account from the App and then downloading books from there. In fact, Amazon has an extensive collection of free books in their library. That in turn lets you try this out without having to spend any money at all on e-books.