Advances in wireless communication systems and mobile devices allow nomad users to participate in mobile collaborative activities. However the availability of hardware resources of the mobile devices that are participating in the collaboration process is a crucial factor that can enhance or jeopardize such activity. This paper studies how the network topology and the hardware resources distributed into a network influence the collaboration among the participants in the activities. The results obtained from simulating the strategy of resource sharing in an overlay network allowed us to observe two clear implications: (1) it is important to maximize the number of links between Desktop PC and mobile devices and (2) the mobile devices have to be placed within the network topology in the nodes with higher degree. According to these observations we have proposed an heuristic for node placement in order to maximize the cooperation level in terms of resource sharing.