The very first transistor was made in 1947 and it has only been 62 short years since its invention. During this time technological advances have made great leaps and bounds and they all owe this to the transistor. Advancements are nearing a plateau as the technology to build transistors reaches its physical limits, and as such, a new component needs to be introduced that can pass the limitations of the transistor. A great candidate is the magnetic-tunneling-junction (MTJ), and only then as a replacement for the transistors digital applications. Already there are many groups designing it physically and finding the best method of production as well as many groups using them to replace transistors in circuits. Thus far, there haven't been any definitive models made of this device to allow simulations of theorized circuits, and the goal of my project since September 2008 has been not only to create a model for the MTJ to use in simulations, but to also simulate a select few theorized circuits to demonstrate the benefit of using MTJ's over transistors. Hopefully through these models and simulations, more innovative designs can come out as they did with the transistor and help keep the pace of our technological advancement to help build better futures for all of us who are alive today, and those who are yet to come into this world.