the present invention relates in general to portable processor based devices that provide computing , communication or entertainment functionality . more particularly , the present invention pertains to portable processor based devices operable while being held in its user &# 39 ; s hand and providing communications , organizer and / or entertainment functions , such as cellular telephones , palm - sized organizers , and mp3 players , and to portable processor based devices providing general computing capabilities , such as laptop or handheld personal computers . more specifically , the present invention relates to systems that detachably mate a plurality of portable processor based devices to provide their combined functionality in an integrated structure .