The P-ISM consists of 5 pen-like devices that provide different functions: a CPU pen, camera pen, virtual keyboard pen, visual output pen with an LED projector, and a phone pen. These pens connect through short-range wireless technology and cellular networks to provide portable computing and communication capabilities. While the concept enables ubiquitous computing, some challenges remain regarding cost, battery life, and usability of the virtual keyboard. The document examines the history and functions of the P-ISM as a prototype for more advanced compact communication devices.