This extravagant wristwatch is an early product designed by Sir Clive Sinclair, who went on to make the successful ZX series of ultra-miniaturized home computers. It was, by all reports, a surprise hit.
8 digits, red LED. ... Launched in February 1977. ... Was available only as a self-assembly kit, by mail order from Science of Cambridge, previously Sinclair Instrument Ltd., which had been founded by Clive Sinclair and to which he moved from Sinclair Radionics. ... Total price was only £11 Sterling (about US$20).
Now a staple of weird wristwatch lists, there remains a certain combination of technical amazement (in its native 1977, it was crazy small) and untrammeled nerdliness that infuses this particular model with an eternal charm. It does not, of course, actually tell you the time.