Total BooX: Pay As You Read

A start-up called Total BooX is going to allow consumers to buy ebooks on a pay-as-you-read basis. In other words, instead of paying for a book upfront like you normally would, Total BooX would have you only pay small fees in increments as you read the book. So for folks who like to start a lot of books and don't finish them, you will no longer need to pay for a full book unless you actually read the whole thing. 

According to the site, the Total BooX app will be available on Google Play early this year. Users will set up Total BooX accounts and use PayPal or credit cards to add to their balance. They can use that balance to set up their own bookshelf and they only need to be online when downloading new books. So far, it's not clear if this will be available on all major devices. 

How does this match up to the free sample downloads that you would get from one of the big ebook stores? Is this something that you think could disrupt ebook sales?