L-Space and Its Subsets

Terry Pratchett has done the hard calculations and given us his theory of "L-Space", that phenomenon known to all frequenters of libraries and used bookstores:

Even big collections of ordinary books distort space and time, as can readily be proved by anyone who has been around a really old-fashioned second-hand bookshop, one of those that has more staircases than storeys and those rows of shelves that end in little doors that are surely too small for a full sized human to enter.

Read more over at Lspace.org.