A number of Call of Cthulhu Keepers these days rely on a laptop computer behind the screen to assist with the paperwork components of running a game or perhaps to play background music for the session. Allicorn, a programmer and Keeper himself, has developed a couple of pieces of free software (for IBM PC compatibles) that you might find useful:

The Keep - A Call of Cthulhu Keeper's Assistant

RPGDeck - A Game audio handler

Read on for more information about these Call of Cthulhu untilities, or simply follow the links above to find out more, direct from Allicorn's web site and to pick up the software.