Dual headed Video Card
It's an AGP card so only Sawtooth owners need apply. But, the advantage to this card is clear... with only 3 PCI and 1 AGP slot on your Sawtooth, you must choose your expansion cards wisely. By getting a 2 headed video card, you can run your 2 monitors and still have 3 slots left over -- you do have at least two monitors, don't you?
Another excellent solution is to get a Voodoo 3 PCI card to drive the extra monitor. The Voodoo 3 is both a 3d card and 2d card, providing VGA output.