In an active WSN where user queries are regularly processed, a significant proportion of nodes relay and overhear data generated by other nodes in the network. In this paper, we propose to exploit this mode of data communication towards a gradual buildup of global knowledge. We show that by harnessing the multihop and multipath communication advantages, only a few user queries in a WSN can lead to an accumulation of accurate global knowledge at node level. This global knowledge can greatly improve numerous WSN applications when used in data validation, event detection, and query optimization.