Amazon is now offering Kindle eTextbook rentals for up to 80% off list price of a printed textbook. You can rent for the minimum length, typically 30 days, with 360 days maximum, and you can extend your rental by as little as 1 day as many times as you want and just pay for the added days. In the middle of a rental if you feel you would like to own the textbook, Amazon will allow you to apply your full rental fee towards the purchase, so no brainner if you were already thinking of buying a Kindle copy. Notes and highlighting can also be performed on rentals and those are accessible even with the retal period has expired.

Note that a Kindle reader (FREE for PC, Mac, iPad, iPhone, Android device, Windows Phone 7, Blackberry) or Kindle-enabled device is required to download and read these eBooks.