Youll need a pretty high geek tolerance level for this very detailed and specialised account of Sir Clive Sinclairs bestselling ZX Spectrum home computer, whose appearance in 1982 with its rubbery keys was thought to be as lovably eccentric as the man himself. But with this he revolutionised the market, educated the British public about the importance of computing, and virtually created the gaming industry from scratch. It was originally to be called the Rainbow in homage to its groundbreaking colour graphics; Sinclair instead insisted on Spectrum as it was more scientific-sounding.Interestingly, the film shows that Sinclairs flair for the home computing market arose from his beginnings in mail order and assembly kits for things such as mini transistor radios targeted at hobbyists, that fascinatingly old-fashioned word. His first home computers were available as kits and to the end of his days, he was more interested in hardware than software; perhaps this intensely serious man never quite sympathised with the gaming culture that drove his product around the world.The ZX Spectrum was many things, but above all it was affordable, and the film shrewdly says that at just under 100, it found the main Christmas present price-point for legions of teenage boys (and it was mainly boys) who were wild with excitement to find one under the Christmas tree. Theres an amusing contribution from broadcaster James OBrien who holds a Spectrum in his hands, closes his eyes and with the aid of this Proustian madeleine, mentally reconstructs every detail of his teenage bedroom.When Sinclair is on screen, his human drama charges the film with interest, but I have to say that the films long central section, simply about all the different games with their blocky 2D graphics, is challenging for non-connoisseurs. But its always interesting to see a film dig into this level of detail, and theres a strong awareness of the kind of art and design work that, without gaming, would never have found an outlet.In the end, Sinclair rather ruthlessly decided not to sell out to his American distributor Timex and instead went into partnership with Alan Sugars Amstrad, which meant laying off a lot of his loyal workforce; and, well, if these newly unemployed people were looking for sympathy from Sinclair, they were to be disappointed. And I would have liked to see Lord Sugar interviewed here about Sinclair. This is an interesting documentary, though one for the heads, as they say.