For a start, it's free. Nought pee. You can just swan through the doors, turn left and there you are. But that's where it gets dark and you immediately start watching people sleeping and wondering exactly what you do when you're snoozing. Ooer.

This is a great exhibition because it explores its subject from every direction, employing not only science but art and folklore, evidence and hearsay, fact and fiction. You will be equally fascinated by popular attempts at staying awake for hours as with the scientific recording of brain waves while sleeping. You'll be entranced by the surrealist Dali nightmare film and you'll try your best not to yawn whilst looking at the The Yawner bust. The children with donkey heads may disturb you, as will the black and white films of sleepers with various sleep disorders (hear them snore!). How awake are you? Test your reactions and learn how to combat jetlag.

This is an all-embracing examination of our need to sleep, the mystery surrounding this unconscious state, our attempts to defy or induce sleep and our need to analyse and explain dreams. The very practical logistics of sleeping are also tackled: bedbugs and the luxury of a bed to oneself. The nomadic bed unit for the homeless is an icon of rocket shaped, streetwise design.

There's no better way to spend an hour or so, whilst spending no pennies. Apart from sleeping, that is.

To accompany the exhibition there's a whole raft of events and tours. Sleeping and Dreaming is on at the Wellcome Collection, Euston Road, until 9 March 2008.

Image of Japanese sleep concert audience by Miyashita Fumio, 1999; Reproduktionen
Nagano (Japan), Biwa Studio, courtesy of the Wellcome Collection.