A Brief History of Planet Earth

The Earth – For Physicists is an article by John Baez with a somewhat unfortunate title. You don't actually need a background in physics to follow this synopsis of the origin and development of our planet.

Definitions in Kindle

Though the Kindle user interface is admittedly rather rudimentary, there's one seemingly minor feature that works great in practice. While reading a document, when you move the cursor onto a word it gives you a one line definition at the bottom of the screen. Hit return and it switches to a screen with the complete definition. I use this feature quite frequently. Even when I'm more or less familiar with a word, it's sometimes nice to check the exact definition. I don't check definitions nearly enough when I read normally, due to laziness, but the Kindle makes it painless enough that I've been actually doing it.