Plans for the "GDrive", previously the subject of rumour among computer experts, were revealed accidentally after notes in a slideshow were wrongly published on Google's site.
The device would create a mirror image of data stored on consumers' computer hard drives, letting users search data stored on other computers via Google accounts.
While offering more convenient access to data, the service will stoke debate about the dangers of storing so much personal data on Google systems. Google recently squared up against the United States Justice Department, which has subpoenaed a limited set of data on Google search habits, drawing an outcry from privacy advocates.
In the presentation notes, the chief executive, Eric Schmidt, made a cryptic comment that one goal of Google was to "store 100 per cent" of consumer information".
A Google spokeswoman declined to comment on any specific service, but confirmed that the presentation containing the notes had been mistakenly released on the internet. "We deleted the slide notes because they were not intended for publication," she said.
"We are constantly working on ways to enhance our products and services for users, but have nothing to announce at this time."
The new service could save computer users from loss of data by keeping a "golden copy" on Google's centralised computers. However, the plan could be thwarted by privacy concerns.
Recently, the Electronic Frontier Foundation, a digital rights advocate, issued a similarly stern warning to consumers to not use such facilities because it would reduce their level of privacy protection.
Google has been at the centre of privacy row in the United States. Last August, Google rejected US government efforts to access its search logs to prop up a contested 1998 law designed to protect minors from objectionable material on the internet.
Microsoft, Yahoo, and America Online have all since admitted that they have provided the government with some of that data from their logs.
The revelations triggered a privacy rights row in Washington that has placed the administration of the president, George Bush, on the defensive and has sparked at least two investigations in Congress.