The 3D components of today's user interfaces are s till underdevel- oped. Direct interaction with 3D objects has been limited thus far to gestural picking, manipulation with linear transformations, and simple camera motion. Further, there are no toolkits for building 3D user interfaces. We present a system which allows experimenta- tion with 3D widgets, encapsulated 3D geometry and behavior. Our widgets are first-class objects in the same 3D environment used to develop the application. This integration of widgets and application objects provides a higher bandwidth between interface and applica- tion than exists in more traditional UI toolkit-based interfaces. We hope to allow user-interface designers to build highly interactive 3D environments more easily than is possible with today's tools.