Web 2.0 provides the technological foundations upon which the crowdsourcing paradigm evolves and operates, enabling enterprises, universities and eGovernments, to access scalable networks of knowledge experts on-line. However, there is no existing practice allowing for coordination of crowdsourcing tasks, and their integration with existing business processes and embedding these services into the Web fabric. In this paper, we examine two applications of enterprise crowdsourcing service in the domain of IT Service Delivery: 1) IT Inventory Management and 2) End-User Support. We illustrate how a) expert discovery mechanism, b) virtual team building capabilities, c) task management and d) provisioning of task-based services, enable enterprises to effectively build knowledge networks, which are able to execute complex and transformative knowledge-intensive tasks. Finally, based on the application analysis, we propose PeopleCloud, an on-demand service system, which spawns and manages scalable virtual teams of knowledge workers by either (1) building on the wisdom of crowds within an enterprise or across a value chain or (2) creating a marketplace for accessing specialists on-line. © 2010 IEEE.