Kindle Sale, today only. $1.99 and up: Top Kindle deals of 2016

https://www.amazon.com/b/ref=amb_...B00O87NWBK

What If?: Serious Scientific Answers to Absurd Hypothetical Questions [Kindle Edition] - $2.99
By the creator of XKCD - Randall Monroe.
https://www.amazon.com/What-If-Sc...00IYUYF4A/
Matches the best price (Jan 2, 2016).