Start-up U3 has announced that products based on its portable drive storage format are to be launched this week.

The format enables users to carry working versions of applications, as well as files, around with them on simple plug-in USB drives.

The U3 format has found widespread support from USB drive vendors, with Kingston Technology, Memorex, Verbatim, and Disgo all announcing drives this week. Software companies backing the standard include AOL, Mozilla, McAfee, Corel, Real, Trend, Ulead, Check Point, and Skype, with more expected to follow.

The "smart drives" are targeted at mobile users who don’t want to carry around a laptop or PDA. Instead, users will be able to take recompiled versions of their favourite programs on the road on a drive outwardly identical to a conventional USB drive, plugging into any available PC as required.

At the point the U3 drives are removed from the host PC, all trace of the software is removed from that machine.

"This will mark the first available plug-and-play way for consumers to carry and access their personal workspace without having to lug a laptop around," said U3 CEO Kate Purmal.

It will be up to companies whether they offer the smart drive versions of their software as paid-for extras, or as an added feature of the standard licence. Microsoft is a conspicuous absentee from the list, though third-party vendors are still likely to offer synchronisation with Microsoft applications such as Outlook.

Anyone purchasing a U3-based drive will be able to find available software for the platform by clicking on a hyperlink embedded in the software toolbar that appears when the drive is plugged into a PC. The same toolbar will operate as a launchpad for the software programs loaded on the drive.

U3 drives will cost more than conventional USB drives, partly because they require a redesigned controller and partly because U3 charges a royalty on every drive. Judging from the launch prices, the premium is modest on a 512MB or 1GB drive, in the order of 10 to 15 percent.

Set up as a joint-venture by rivals SanDisk and M-Systems, the company has always been expected to stand on its own financially. The company has been working hard on the technology since its founding last year, getting the smart disk standard agreed in record time.

As is common with storage standards, there is a rival to U3, the Drive Alliance standard, backed by Lexar and Samsung, which published its portable application spec last December. The latter currently trails U3, but could work out slightly cheaper as it will not add royalties.