As Web service technology evolves, the idea of context-aware services gains more interest. An idea is that different sets of services will dynamically drop into the mobile users? devices depending on their contexts. To do this effectively requires location modelling and representation as well as spontaneity in downloading and executing the service interface on a mobile device. This paper introduces the concept and an implementation of Hanging Services that supports proactive and ad hoc context-aware services in mobile environments. This system works on top of an 802.11b Wireless network. The prototype implementation is done using Web services and highly compact mobile code applications using Microsoft .NET Compact Framework.