I've started reading through some of the classics you can get for free for your Kindle. Till then I never knew The Time Machine was such a short book, perfect for some casual 2 day reading.
This is a simple yet exciting adventure story that draws an image of the possible future where our society could be heading. Also, it's hard not to like a story where the main character is a classy fellow who travels through time in gentleman's clothes from the 19th century.
Something you can read over and over again, even when you should be busy doing other things.