The BlackDog is a pocket-sized, self-contained computer with a built-in biometric fingerprint reader which was developed in 2005 by Realm Systems, which is plugged into and powered by the USB port of a host computer using its peripheral devices for input and output.
It is a mobile personal server which allows a user to use Linux, ones applications and data on any computer with a USB port. The host machine's monitor, keyboard, mouse, and Internet connection are used by the BlackDog for the duration of the session. As the system is self-contained and isolated from the host, requiring no additional installation, it is possible to make use of untrusted computers, yet using a secure system. Various hardware iterations exist, and the original developer Realm Systems closed down in 2007, being picked up by the successor Inaura, Inc.
Identified as the BlackDog, the Project BlackDog, or Original BlackDog, the first hardware version was touted as "unlike any other mobile computing device, BlackDog contains its own processor, memory and storage, and is completely powered by the USB port of a host computer with no external power adapter required." It was created in conjunction with Realm System's Project BlackDog Skills Contest (announced on Oct 27, 2005) which was supposed to raise interest, and create a developer community surrounding the product. The BlackDog was publicly available for purchase from the Project BlackDog website in September 2005 for those who wished to enter the contest or to experiment with the platform. Production ended in mid January 2006 when the contest closed.