ZX81: The $99.95 personal computer A US advert introducing the Sinclair ZX81 in kit form, from the days when it was still not uncommon to purchase your computers in bits (in order to save money - $50 in this case) and get your own soldering iron out to stick it together. At least Sinclair made it easy as their ability to sell computers so cheaply was based on their knack of getting the number of components down to the bare minimum - the ZX81 only had four chips on it, and relatively few additional components (the advert is probably fairly faithfully showing the actual components from the kit). The kit-form ZX81 retailed for $100, which is about [[66|1981]] in [[now]] terms. This was nearly a third the price of one of its competitors, launched in the same year - the Commodore VIC 20.