Obsessive fans are nothing new - in Greek myth, for example, when Orpheus refused to sing for the Maenads, followers of Dionysus, they tore him apart, leaving his head to float down the river Hebrus, singing as it went.  Over the last 30 years the novelist Russell Hoban has alluded to and reworked this myth again and again; fortunately his own obsessive fans, perhaps mollified by his continuing productivity, have been more benevolent.  For some years a number of them have celebrated his birthday, 4 February, by clubbing together to buy him some flowers and a bottle of malt whisky: last year it was Bowmore; this year Glengoyne.  But among the Hobanites who congregate on the Hoban-dedicated newslist The Kraken a feeling arose that this wasn't enough.  One of them, Diana Slickman, of an experimental Chicago theatre group called the Neo-Futurists, came up with the idea of writing out favourite Hoban passages on pieces of yellow A4 paper (a recurring motif in Hoban's work: he says that a blank sheet of yellow paper is less intimidating than a blank sheet of white paper) and placing them in public places for passers-by to stumble upon.

The SA4QE (Slickman A4 Quotation Event) is now in its third year, with Hoban quotations being distributed as far afield as Sydney, New York and Vienna.  The project has its own website, run by Richard Cooper, who I met outside the Cheshire Cheese in Crutched Friars (the name of the street), the site of a significant encounter in Hoban's 1974 novel The Medusa Frequency.  It is just north of Tower Hill tube - the London Underground is a recurring location in Hoban's work - and round the corner from the Orpheus bar-restaurant.

Cooper finds it hard to pin down why Hoban exercises such a grip on some of his readers: it varies, he suggests, according to which book you started with.  For most people this is Riddley Walker, his 1980 fantasy written in an invented language, a degenerated English that contains in its vocabulary and structure a potted history of nuclear apocalypse and collapsing civilisation.  Cooper's own start came with The Medusa Frequency, which he read in 1986 or '87, when he was about 16.  It was as if, he says, the Dickens and Golding he had been doing at school were in black and white: Hoban was in colour.

The Medusa Frequency tells the story of Herman Orff, a blocked writer who begins having conversations with the Kraken, a sea-monster from Scandinavian mythology, via his computer at three o'clock in the morning (a recurring time in Hoban's work).  Recently, inspired and encouraged by Hoban, Cooper quit his job to write a novel, which is about a young writer who quits his job to write a novel.  Cooper promises that most of it is made up.

Last year Cooper took the day off work and performed a pilgrimage around the capital, beginning at 6.45am and ending towards nine in the evening, visiting Hoban-related sites and leaving his bits of yellow paper.  This year, he was taking a more casual approach, distributing his quotations (or "4qating", as the Hobanites call it, 4qate being the verb form of SA4QE) as and when he saw fit - a practice more in keeping with the Slickman ethos.  Another important aspect of 4qating is that the papers should not just be left around as litter: they should be deliberately placed.  If you come across a piece of yellow paper wedged into a phonebox or slipped behind a poster on the Underground, you will know what it is.  Cooper deviates from standard practice in one respect: he types out his quotations rather than writing by hand, because he is worried that his illegible handwriting might cancel out and possible benefits from the exercise.

Whether there are any benefits to the public at large is open to question.  On the SA4QE website Cooper keeps records of 4qating exploits from fellow eventers; so far he has had no responses from members of the public inspired by a chance discovery.  The one person who does benefit is Hoban, who writes every year thanking his fans for their support - it gives him, he says, the kind of lift an athlete gets from an enthusiastic crowd.  He seems to mean it.  Then again, perhaps he just wants to hang on to his head.

Robert Hanks