Physically large displays are becoming prevalent in the workplace. Although many researchers have articulated qualitative benefits of large displays, little has been done to quantify and exploit these benefits. In the first part of my talk, I will show that information elicits fundamentally different cognitive reactions when presented on a large wall-sized display as compared to a smaller display, even when viewed at identical visual angles. I will describe a series of experiments that show how physically large displays immerse users within virtual environments and increase performance on certain kinds of spatial tasks. In the second part of my talk, I will present WinCuts, an interaction technique designed to support collaboration on large displays. This technique allows users to easily create live replicas of arbitrary window regions. Each of these replicas, which we call a WinCut, may be used locally or displayed on a remote machine. I will discuss how this technique is useful in a wide range of scenarios including both single and multiple devices.