h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

There can be few things more heart rending than parting with a pair of much-loved pyjamas. They may be shabby, often replete with holes in the knees, but they have subtly become exactly the right shape, and some of your personality has worn off onto them.
Personally, I feel that brushed cotton is the only truely correct fabric for pyjamas.

Could well be, although it depends on what you like. I prefer cotton but I know some that certainly prefer silk or similar. Synthetic fibres are generally not agood idea though. Unless you like that sort of thing.