In this paper, we propose to use P-VoT (POSTECH Virtual reality system development Tool), a component based interactive authoring toolkit for virtual environments, to quickly build a virtual ubiquitous computing environment. We have created four sets of components in P-VoT for this purpose: (1) sensors, (2) displays, (3) processing objects, and (4) data collection objects. The first three types of objects are used for quickly prototyping and planting ubiquitous computing subsystems in the virtual environment. They are easily reusable within P-VoT and can be adapted as needed: its function or behavior can be altered easily at different levels of abstraction. The data collection objects are used for collecting usability data such as performance measurements and survey answers. Such a virtual ubiquitous computing environment can be effectively used for system architects to walk through and present various scenarios, to validate interaction usability and simply as software testing platforms.