The Pebbles research project is investigating how the functionality and the user interface can be spread across all of the computing and input / output devices that one or more users have available. In this way, the hand-held devices can be used to augment the other computers rather than just being a replacement when other computers are not available. As part of this research, we are looking at how multiple people can use their hand-helds to share control of a main computer running either legacy applications, or custom multi-person applications. We are also looking at how information and control can be fluidly moved between the main screen and the individual hand-held screens.