Cheers to James our server guru for spotting this one. Remember the Matrox TripleHead 2 Go we recently tested ?
SoftTH - Software Triplehead is a tool that allows allows using three monitor "triplehead" with Direct3D 8 and 9 games without special hardware. You need three monitors attached to PCI Express video cards. Only one card does all the rendering work, so secondary card can be a low end card, only Direct3D support is required. SoftTH works by rendering the whole scene on one display adapter, which then gets split into three parts to be displayed on each monitor. While it is technically possible to use it on a AGP/PCI card, only PCI Express has the required bandwidth to get good framerates.