I don't think this one needs any introduction. Grab your towels!
Far out in the uncharted backwaters of the unfashionable end of the Western Spiral arm of the Galaxy lies a small unregarded yellow sun. Orbiting this at a distance of roughly ninety-eight million miles is an utterly insignificant little blue-green planet whose ape-descended life forms are so amazingly primitive that they still think digital watches are a pretty neat idea.
The Hitchhiker's Guide to the Galaxy
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It's an ordinary Thursday lunchtime for Arthur Dent until his house gets demolished. The Earth follows shortly afterwards to make way for a new hyperspace bypass and his best friend has just announced that he's an alien. At this moment, they're hurtling through space with nothing but their towels and an innocuous-looking book inscribed with the big, friendly words: DON'T PANIC.