Cluster computers are seen as expensive, space consuming, high energy platforms hidden away in universities and tech companies. Having your own cluster computer to explore parallelism ideas was not realistic for the majority of people. With the release of the Raspberry Pi things changed, and now it is possible to build a five node machine powered by USB that you can hold in your hand for as little as £120. This talk will describe how such a machine can be built with very little technical knowledge, and then provide an example of setting up MPI on the machine to allow simple distributed parallel applications to be explored. The system is not fast, and communicates via a shared USB 2.0 connection, but the principles of distributed parallelism can be explored. An example system will be available for demonstration purposes.