The Kindle Paperwhite is the e-reader I usually recommend to people looking for an Amazon e-reader because it's got all the features you want in a Kindle and isn't as expensive as the higher-end Voyage and Oasis. When recommending it to folks I always add, "It goes on sale from time to time, so you may want to wait."
Well, today it's on sale -- and today only -- for $90, which is $30 off. That's about as low as it gets.
The entry-level Kindle is also on sale for $30 off. It's usually $80 but today it's $50. It's a perfectly good e-reader but doesn't have an integrated light.
Amazon hasn't refreshed these more affordable Kindles for a while. Rumor has it a new Paperwhite will be released this summer with a new lighting system and support for listening to audiobooks via Bluetooth.