'How do you store an encyclopedia on a toothpick?' This theoretical puzzle is used by Haruki Murakami in his wonderful novel Hard-Boiled Wonderland and the End of the World to illustrate a point about eternity.

The theoretical answer to the puzzle is as elegant as it is simple.

To store an infinite amount of data on a toothpick, assign a numerical value to each letter of the alphabet (00 for 'a', 01 for 'b' and so on) - you could even use their ASCII codes. Next string all the letters making up the encyclopedia together to form a very large number. You'll end up with something like this 0419041713081924...
Next turn this number into a fraction by pre-pending a 0. to it and make a mark on the toothpick at exactly this point of its length (where 0 is the start of the toothpick and 1 is its end). This mark contains all the information of the encoded encyclopedia in its position.

Obviously this solution is not practical, but it does show how infinity (or eternity) is not necessarily a matter of size, but a matter of precision. What Murakami suggests with this puzzle is that experiencing eternity is not necessarily about living forever, it is about the level of detail at which you experience one moment.

see also: Zeno's Paradox

amnesiac said 're Encyclopedia on a Toothpick: cool! is the book good?'

I said 'very good, one third Ghost in the Shell, one third Princess Mononoke, one third Paul Auster'

Excalibre said re Encyclopedia on a toothpick : of course, even in theory this falls apart, as there is a planck length, something like 10^-35 meters, and there is no smaller meaningful unit of distance. you _can't_ get smaller than that. so your encyclopedia would have to be less than 35 digits worth of information (assuming your toothpick is no longer than a meter.) there IS such a thing as infinitely small, and it's bigger than you assume.