wxMaxima is a cross-platform graphical front-end for the computer algebra system Maxima based on wxWidgets. It provides nice display of mathematical output and easy access to Maxima functions through menus and dialogs.[Download]
The free software called R can be an alternative for private researcher or
personal computers, since the other products are not really cheap. R is somewhat complicated at first glance. However, once you get used to its syntax, it might be a very useful software. There is a large internet community offering a lot of additional packages, which help you to carry out your analysis. One big advantage of R is that it is not only an econometric software, you can also run simulations, do statistics and computation.[Download]
I strongly encourage users of R to install RStudio. RStudio is a very user friendly user-interface for R. You have to install first R and then RStudio. Especially for newcomers to R this software package is of tremendous help!
A powerful LaTeX processor for Windows. It is needed to run for instance TeXnicCenter. [Download]
A simple, intuitive and efficient editor for your LaTeX documents. It features syntax-highlighting, spell-checking and direct compliation of your LaTeX files. [Download]