Screen spanning doctor

Screen spanning is the act of running more than one independent monitor, which can be very nice if you need to preview web sites while coding them, or just need a lot of screen real estate. Powerbooks and G3 and G5 towers all support screen spanning out of the box. iBooks and iMacs have the feature crippled: the video output of these machines mirrors the main screen. This may be great for hooking a machine up to a presentation projector without configuration hassles, but leaves something to be desired for some users.

Screen Spanning Doctor offers a nondestructive way to disable the restriction, on machines with graphics cards that can handle the extra real estate (list of supported machines). It is basically nothing more than a script that sets some options in Open Firmware and resets the machine. I tried it on a 15" flat-panel iMac with a 15" external monitor added: the machine did appear to be less stable after the patch but this may have been coincidental, as its motherboard turned out to be faulty.