One of the first Apple computers that company founder Steve Jobs sold from his parents’ garage is expected to reach up to £80,000 at auction - 190 times its original price.
Jobs famously invested all he had to finance the first Apple creation, selling his VW van.
Around 200 original Apple 1s were designed and hand-built by Jobs’ friend and co-founder Steve Wozniak.
It launched in 1976 but few remain.
The £420 Apple 1 did not have a keyboard or monitor, meaning users had to supply their own.
It also had a tiny 8K memory - minuscule by today's standards, where the latest iPad comes with 64Gb of memory.
However, the Apple 1, the forerunner of the Mac, iPod, iPad and iPhone, has proved a good investment.
The iconic original is on offer at a Christie’s auction in central London on October 9 and comes from the estate of Joe Copson, a former Apple employee.
The rare opportunity to buy an original is expected to attract worldwide interest from museums and private technology collectors.
Christie’s scientific specialist James Hyslop said the computer’s pre-sale estimate reflected a growing interest in early computer technology.
He said: 'This is the computer that started Apple, now recognized as the most valuable company in the world.
'Its significance in making computer technology accessible for all cannot be undervalued.'
Before the Apple 1, anyone wanting a computer had to solder it together themselves.
The Apple-1’s fully assembled motherboard made it ready to use straight from the box - provided the buyer supplied their own keyboard, power supply and display.
Launched in Palo Alto, California, in July 1976, it was priced at $666.66 (£420) - reportedly because Wozniak liked repeating digits.
Jobs sent them direct to buyers from the garage of his parents’ house.
It is not known how many were sold but by April 1977 the price had dropped to $475 (£300).
The computer helped kick-start a technological revolution that brought affordable computers out of science labs and into people’s homes.
The Apple II was introduced in April 1977 with an integrated keyboard, sound, a plastic case, and eight internal expansion slots.
By the time it was discontinued in October 1977, around 200 Apple 1s had been produced.
It is thought that only 30 to 50 of the computers still exist today and there is rarely an opportunity to buy one.
Jobs met Wozniak at high school in the early 1970s.
They decided to set up their own company and create a personal home computer.
Jobs’ talent at marketing and selling Wozniak’s designs helped him turn Apple into a global company.
Earlier this year a rare working Apple 1 computer has been sold at auction in New York for $374,500 to an unidentified bidder, leaving the previous record price of $212,000 in its wake.
One of only two hundred built in 1976 by Apple co-founders Steve Jobs and Steve Wozniak, auction house Sotheby's had previously estimated the iconic Apple 1 would fetch $180,000.
The unexpectedly large sale was put down by Sotheby's to a bolstering of public interest in Apple's history since Jobs' death last year and the fact that of the 50 Apple 1's left in existence, only a handful are still working.