ZX Spectrum +

By 1984 the original Spectrum's rubbery keyboard, for all its charm, was starting to feel its age. The Spectrum + answered the grumbles by dropping the unchanged 48K internals into a new case with a proper full-travel keyboard, a reset button and an altogether more serious, professional look.

Inside, it was the same machine millions already knew and loved, fully compatible with the Spectrum's vast library of games. Nothing about the experience changed; it just felt a little more like a piece of equipment and a little less like a toy, which was rather the point.

It was a sensible mid-life refresh rather than a reinvention, buying Sinclair's best-seller more time at the top while looking smarter doing it. It also paved the way for the more thoroughly redesigned Spectrums that followed, as the famous machine settled into a long and productive middle age.