Fedora 8 ships XRandR 1.2 (the X Rotate and Render Extension), which makes it possible to render a screen onto an overhead projector, among other things. Here’s instructions on how to do useful things with XRandR (not Fedora specific). For now, control of XRandR is handled through the command line. In Fedora 9 or 10, there will likely be better user interfaces to configure XRandR.