The Limulus project goal is to create and maintain an open specification and software stack for a personal workstation cluster. Ideally, a user should be able to build or purchase a small personal workstation cluster using the Limulus reference design and low cost hardware. In addition, a freely available turn-key Linux based software stack will be created and maintained for use on the Limulus design. A Limulus is inteneded to be a workstation cluster platform where users can develop software, test ideas, run small scale applications, and teach HPC methods.