ZX Spectrum 48K
Rubber keys, a tape deck, and eleven minutes of hoping.
Sinclair's £175 home computer put programming into British bedrooms and created an entire games industry.
You typed LOAD "" and pressed play on a cassette recorder, then watched coloured stripes for eleven minutes, and roughly one time in four it crashed at the end.
The rubber keyboard was horrible and the colour clash was worse, and it did not matter, because everybody who had one learned a bit of BASIC whether they meant to or not.
Cost back then
£175
Goes for now
£80–£400 depending on condition and boxing
