Photocopier
The office machine that makes another of whatever lands on the glass — analog optics for thirty years, nowadays a scanner and a laser printer sharing one enclosure.
The Xerox 914 turned xerography into an automatic plain-paper machine in 1959, and for three decades the copier stayed analog: lamps, mirrors and a lens exposed the photoreceptor drum straight from the original. Digital copiers in the late 1980s swapped the optics for an image sensor and printed with a laser — at which point the boundary between printer, scanner and fax dissolved into the multifunction machine.
Going digital brought two quirks. Modern copiers recognize banknotes and simply refuse to copy them. And since every job is buffered on an internal hard drive, retired office copiers have become an unexpected gold mine for whoever buys them at auction — years of contracts, medical records and payrolls included in the price.