Inventors at Dyson secretly developed their own version of Google's glasses 13 years ago but dropped the idea to concentrate on other things, the firm has revealed.
Sir James Dyson's company, which has its headquarters in Malmesbury, also invented a special filter to make diesel engines cleaner, as well as a digital motor that would work on hydrogen fuel.
The three never-before-revealed inventions never quite made it to full production, and have only been revealved now to mark the 21st birthday of the engineering firm most famous for its bagless vacuum cleaner.
It has since launched bladeless fans and heaters, as well as high-speed hand-driers and even a tap that dries hands.
Sir James now hopes a £250m expansion will see the creation of 3,000 jobs with the intention to double the size of its R&D facility.
Of the inventions that never made the grade, the one which has similarities to Google's Glass is the Dyson Halo from 2001, which went by the code-name N066.
An "augmented reality goggle set", it featured a full colour 3D "heads-up" display which was attached to a mobile phone-sized device that could be carried in the pocket.
Google's Glass features what is effectively an internal computer and communications device.
Dyson's prototype went even further than Google Glass does now – the user could turn any flat surface like a table into a touch-sensitive computer and keyboard, just by looking at it.
"In the prototype, the user could see and use several different key applications," said a Dyson spokesman.
"A virtual personal assistant, similar to Siri, could read out emails and interpret basic voice commands.
"The prototype incorporated a solid state gyro. This allowed virtual objects to be pinned to reality when moving head up/down or left/right. This enabled a keyboard to be projected in front of the user so that one could type and write emails on any surface."
But despite working on the device for three years, a decision was taken not to go from prototype to full production, and instead some of the technology went on to be incorporated into other Dyson products.
Two other inventions that never made it were in for engines.
The first, a diesel trap with the codename X007, attempted to use the cyclone technology Dyson invented for a vacuum cleaner but on filtering out the polluting particles in diesel engines.
The spokesman said: "Initial prototypes focused on cyclones but the required energy consumption was too high.
"Condensing oil onto the small particles to increase their radius came next.
"But the particle size was inconsistent, allowing inaccurate results, so the focus turned to the use of electrostatics and the final system used an electrical discharge to ionise and collect these particles which were then burned off in an oxygen rich environment.
"All too similar to James Dyson’s battle with the vacuum cleaner bag market, manufacturers were not interested in the technology instead turning to ceramic filters.
"Diesel engines now use particulate filters which clog, and as a result drop in performance – the clogging particles are regularly burned off to improve efficiency."
The third invention is a digital motor to fit in a hydrogen fuel cell motor, but it never made it to full production.
Hydrogen fuel cells convert chemical energy from hydrogen and oxygen into electrical energy but require a large, constant source of both hydrogen and oxygen to run, but produce electricity continuously as long as these elements are supplied.
"For three years, ten Dyson engineers worked to adapt a Dyson digital motor so it could sit at the heart of a fuel cell," said the spokesman.
"The aim was to increase performance whilst reducing size. The results were impressive.
"The compact, lightweight and highly efficient digital motor V4HF resulted in a 20 per cent increase in power density and improved efficiency. The start-up time became almost three times faster."
Dyson engineers are still exploring other possibilities for the Dyson digital motor.