It almost goes without saying that the Internet lends itself naturally to Blake - he was, in the words of artist Stan Peskett, "the world's first multi-media artist". The spirit of dissent and eclecticism that characterises the Net would surely have appealed to his anti-establishment tendencies.
As things stand now, a visit to the various (exclusively American) Websites connected with Blake proves them to be a bizarre combination of batty mysticism and dry academic research, with an especially large Blake project currently under way at the US Library of Congress. Every image and word Blake wrote, etched or drew is available for downloading. "We're still exploring him," says Adrian Mitchell, who has just staged a re-write of Tyger in Boston. "He's centuries ahead of us."
The poet Michael Horowitz has written on several occasions about Blake's technical innovations being rediscovered in 1960s San Francisco and, even today, the curator of the Blake collection at the Tate Gallery will tell you that expert opinion remains divided over exactly what it was that Blake did to achieve some of his more striking chromatic effects in such prints as Isaac Newton. Referring in a recent Spectator review to hippie fanzines, Horowitz has noted that "overlapping with inventive graphics and multiple colour-screening being introduced to record and book cover design... [were] anticipated by W Blake 200 years ago." A self-publisher who worked from home, a political subversive and songwriting polemicist, a multi-media artist, Blake was developing what was, in effect, the first Website in history 200 years before the technology was available.
Blake's enthusiasm for the American Revolution knew no bounds and he has always been popular with Americans. The late Allen Ginsberg, in particular, helped to introduce him into pop-culture in the Sixties, where he remains, rather like Ginsberg himself, an icon of counter-culturalism. On Ginsberg's final visit to London last year, the guru of Beat was thrilled to discover that the church of St James's, Piccadilly - where he was giving a reading - was the very building where the infant Blake had been christened. As usual, Ginsberg finished off his reading with a sung version of a Blake poem, the final line of which - "and all the hills echoed" - he repeated happily over and over again (the more reprises, generally speaking, the more successful he felt the reading had been).
Ginsberg famously had a vision of Blake in a New York tenement flat in 1948. Ginsberg, in some kind of trance, "heard the voice of Blake" intoning several poems, including "Ah! Sunflower!" (later reworked by Ginsberg into his "Sunflower Sutra"). Ginsberg was always a bit vague about the voice of Blake, with its sonorous timbre. Of course, many people would like to know what he sounded like. "Did he have a Cockney accent?" asked Blake biographer Peter Ackroyd cheekily, when told of Ginsberg's epiphany.
On his first visit to England in 1958, improbably lunching with Edith Sitwell at her "ladies' club", the youthful Ginsberg was shocked to discover that his idol was "not considered 'mature', so to speak, by the wits of Oxford". But this only confirmed Blake's status; Blake was still overlooked by the arbiters of taste, dismissed as a peddler of children's ditties and mad, god-infested versions of his nefarious hallucinations. Things have changed since those times; Blake can now be happily quoted on the 1995 Glastonbury Festival poster, yet can spawn more PhD dissertations than any comparable writer. Billy Bragg can glottal-stop his way through "Jerusalem" (for a century mistaken as a paean to Empire that raised the rafters of public school chapels) and Van Morrison can pay obeisance to his godliness; yet, at the same time, Dmitri Smirnov, a Russian emigre composer who came to England specifically to live in the country of Blake, can write heavily mystical Blakean operas like Tiriel, staged to rapturous applause in Freiburg in 1989. According to figures compiled by Donald Fitch, of the University of California Press, between 1970 and 1979, a total of 636 Blake poems were set to music and given public performances. The American composer William Bolcom has set to music the complete Songs of Innocence and of Experience, a work that lasts some three hours in performance.
In the materialistic Eighties, interest in Blake dwindled, but it has now come galloping back to the fore. A number of venerable Blakeans like Adrian Mitchell, Allen Ginsberg and Mike Westbrook have simply been rediscovered. Others, like the artist Stan Peskett, have come to Blake late in life. Peskett has recently been painting Blake-influenced murals in public areas of Peckham where Blake lived (and saw angels) as a child. But Blake has always remained a presence in the life of jazzman Mike Westbrook. "As you get older, Blake seems more and more relevant," he observes. His former collaborator, Adrian Mitchell, has re-written his Seventies play Tyger as Tyger Too. He has sharpened some satiric aspects to attack the likes of "Damien Hirst and other glorifiers of death" in the sepulchral new figure of Gloat, who manages to "pickle Blake and his wife, though they come back to life".
Mitchell is drawn to the childlike, sunny-side-up aspects of Blake, but Blake is not all nurses' songs and flower power. Some of his darker poems and more striking prints have a disturbing quality; his image of the spirit of a flea has an almost Kafkaesque tinge to it. The whole notion of "cleansing the doors of perception" is a Blakean adage taken up and partially distorted by drug culture. Tim Heath, who has set up a design company in Blake's former dingy lodgings (now in a street full of expensive designer-wear stores) to finance a "centre for the dissenting imagination", occasionally turns over his business premises for exhibitions of specially-commissioned pieces. One exhibition - of artists' genitalia (Blake was particular in his pursuit of sexual liberation) - caused a furore among the more staid Blakeans, and a planned next exhibition of "the gift of depression" is hardly likely to endear him to Mitchell and his "I think some art is harmful but I'm not into censorship" stance.
Last year, after releasing his album of Blake songs, Jah Wobble made a pilgrimage to the Blake House - a journey that Ginsberg never got around to making himself. Ginsberg had talked about Blake with his friend Johnny Depp and it was therefore no surprise to find Depp cast as "William Blake" in Jim Jarmusch's film Dead Man, in which a 19th-century Native American becomes convinced that the listless Depp is the fettered soul of the great bard, whom he must help to die. Jarmusch, too, was a friend of Ginsberg and the Dead Man Website has directed a legion of teenagers towards non- schoolroom Blakean culture.
From anti-establishment rockers The Fugs to the former chairman of British Rail, Sir Peter Parker (patron of the Blake Society), the admirers of Blake are varied indeed. But "Blake's wings are broad enough to stand it," says Adrian Mitchell, using a suitably angelic metaphor.
Stan Peskett is perhaps the most eloquent of all when it comes to Blake's modern appeal in the age of Baudrillard ("culture is the consumption of symbols"). "We're living in similar times to Blake, with a new industrial revolution about to kick in. He was a media frontiersman long before people could even imagine it, and he would have been there on the Net, devising metaphors and symbols."
But would Blake really be on the Net or would he be down a hole with Swampy? "He would certainly find plenty of things to be angry about right now," muses Peskett.
'Bright as Fire: The Westbrook Blake' is at the Salisbury Festival tomorrow, 8pm. Booking: 01722 320333