Wolfram Research Mathematica v7.0 for Windows XP

If you're doing anything technical, think Mathematica - not just for computation, but for modeling, simulation, visualization, development, documentation, and deployment.

Why Mathematica? Because this one integrated system delivers unprecedented workflow, coherence, reliability, and innovation.

Rather than different toolkits for different jobs, Mathematica has been built ground-up over nearly 20 years to deliver one vision: the ultimate technical application and environment.

Following closely on the dramatic reinvention of Mathematica in 2007, Mathematica 7 continues the momentum of innovation to deliver an array of new capabilities, greatly extending the state of the art in many areas, and bringing a dozen major new application fields into the integrated framework of Mathematica.

More info: http://www.wolfram.com/products/mathematica/index.html

Installation instructions:
1. Install software start first with autorun.
2. Run software and select the option to license it
3. Launch keygen and enter the license number from keygen into Mathematica
4. Click Next enter the MathID from Mathematica into keygen
5. Click Generate and you'll get the password which you'll have to enter into Mathematica.