In this work, we study ways to use a portable projector to extend the workspace in a perspective corrected multi display environment (MDE). This system uses the relative position between the user and displays in order to show the content perpendicularly to the user's point of view in a deformation-free fashion. We introduce the image created by the portable projector as a new, temporary and movable image in the perspective corrected MDE, creating a more flexible workspace to the user. In our study, we combined two ways of using the projector (handheld or head-mounted) with two ways of moving the cursor on the screens (using a mouse or a laser-pointing based strategy), proposing four techniques to be tried by the users. Also, two exploratory evaluation experiments were performed in order to evaluate our system. The first experiment (5 participants) aimed to evaluate how using a movable screen in order to fill the gaps between displays affects the performance of the user in a crossdisplay pointing task; while the second (6 participants) aimed to evaluate how using the projector to extend the workspace impacts the task completion time in an off-screen content recognition task. Our results showed that while no significant improvement of the performance of the users could be seen on the pointing task, the users were significantly faster when recognizing off-screen content. Also, the introduction of the portable projector reduced the overall task load on both tasks.