IBM Japan Ltd. said Wednesday it has developed a prototype of a compact portable computing device that allows users to carry their software to locations equipped with dedicated cradles.

The small device, tentatively named the PC Core System, measures only 8.2 × 16 × 2.2 cm, weighs 300 grams and contains a processor, memory and hard-disk drive, said Akihiro Shimoide, a spokesman at the Japanese unit of U.S. computer giant International Business Machines Corp.

It can be operated by inserting it into a cradle to connect it with other computing devices, including personal computers and keyboards.

"The PC Core System introduces the concept of a main computer unit that can be put on and taken off," he said, adding that the device is based on the Meta Pad, which has been developed by the U.S. parent company.

The trial version is targeted exclusively at corporate users, and IBM Japan has no intention to sell it to general consumers, he said.

It is being shown to IBM Japan corporate customers during a three-day publicity event that started in Tokyo on Wednesday.