BleepingComputer.com: Controling my fighting robot

Ok this sounds strange but its a project for school where we take a box of random pc crap and build something out of it. I'm using the fans as wheels for a fighting battle robot I'm making. Are there any programs that can instantly let me control the speeds of the fan (So I can steer) also one that can control all of the fans so I can have an extra one to control a spinning saw blade (actully a sharpend hard disk)