The recent trend towards miniaturization of projection technology indicates that handheld devices will soon have the ability to project information onto any surface, thus enabling interfaces that are not possible with current handhelds. We explore the design space of dynamically defining and interacting with multiple virtual information spaces embedded in a physical environment using a handheld projector and a passive pen tracked in 3D. We develop techniques for defining and interacting with these spaces, and explore usage scenarios. ACM Classification: H5.2 [User Interfaces]: Interaction styles. I.3.6 [Methodology and Techniques]: Interaction techniques. General terms: Design, Human Factors