We’ve seen computer mouse calculators from Ezkey and Lexibook. Qmemory decided to use a USB drive for the mathematical calculations device instead.
You won’t be able to fill it up with that much data though, since the memory capacity is only 256MB. It supports USB 2.0 and measures 85 x 53 x 6 mm.
The Qmemory USB CardDisk ($14.95) is available at FlashMemorystore.com. (Update: Link removed because the page is gone.)