A new utility could make U3 'portable program' drives a lot more viable because it configures software to run on the devices..

A U3 drive in theory allows you to carry your favourite programs around and use them on any PC you plug it into.

The major snag is that the U3 only works with compatible programs, or software that has been specially tweaked. This is because most programs look to the host PC's Registry for file locations and other configuration information.

Now Scottish software house Runtime Revolution has produced a utility called U3 Package Prototyper, which is designed to allow developers to make their software U3 compatible.

But Runtime managing director Kevin Miller said it is simple enough for others to use. "The reality [is] that end users have been wrapping applications and while there is no guarantee they will work, most of them do. We've seen people wrap many mainstream applications."

The utility is available as a free download to people registered with the U3 developers site – and registration is free. It is billed as beta code but Miller said in fact it has been finalized.

He added: "Because of this popularity the next step is that we will be releasing this utility on the 'main' U3 software site as a free download for any U3 user -not just developers. That should be happening at some point next week. "

RunTime is offering another U3 utility called AppSnapper that gets round another limitation of the technology by ensuring that if you click on a file it launches the relevant application on the US, not the host PC.

It includes a third utility called CrashZapper that cleans up information on the host computer in the event of a system crash.

AppSnapper, usable on up to three U3 drives, costs $9.95 (about £5) from the U3 Software Central Store.