If you're looking for an e-reader, it doesn't get much better than a Kindle, especially now that you can get one on sale. Right now, the base Amazon Kindle starts at just $64.99, and the higher-end Paperwhite now starts at $89.99.
The current model of the regular Kindle was released in April, and it features a 167 ppi screen with a built-in backlight, white and black colors, and 4GB of internal storage. If you have an Audible subscription, you can connect Bluetooth headphones or speakers to listen to audiobooks. The version with advertisements on the lock screen ("With Special Offers") is $64.99 ($25 off), while the version with no ads ("Without Special Offers") is $84.99 ($25 off).
The Paperwhite bumps up the screen to 300 ppi, adds waterproofing, and doubles the storage to 8GB (a 32GB version is also available). It comes in black and blue colors, instead of the black and white colors of the base Kindle. The version with special offers is $89.99 ($40 off), and the version without special offers is $109.99 ($40 off).
You can grab either of the models at the links below. The sale is live at both Amazon and Best Buy, though Best Buy only has the versions with advertisements.