OpenStat:  ein allgemeines Statistik-Paket für Windows und Linux, entwickelt von Bill Miller von der Iowa State University, mit SPSS-ähnlicher Benutzerschnittstelle. Ein Handbuch im Pdf-Format ist vorhanden.

ViSta: ein Statistikprogramm mit graphischer Benutzeroberfläche für Windows, Mac und Linux/Unix. Der Schwerpunkt der Software liegt auf der Datenvisualisierung.

Das Statistiklabor, entwickelt am Center for Digital Systems (CeDiS) an der FU-Berlin, ist ein R-basiertes Windows Programm primär für den didaktischen Einsatz. Einfache oder auch komplexe statistische Probleme können mit Hilfe des Statistiklabors simuliert, bearbeitet und individuell gelöst werden.
Vielfältige grafische Darstellungsvarianten ermöglichen dabei jederzeit anschauliche Visualisierungen der zugrundeliegenden Daten.

ADE-4 (2004)  Statistische Software für multivariate Analyse und Graphik. Freewaredownload für Mac und Windows

DATAPLOT (2002)   Software für wissenschaftliche Visualisierung, statistische Analyse und nichtlineares Modellieren . Freeware für Unix, VMS, Linux, Windows. 

R: eine Programmiersprache und eine Umgebung für das statistische Rechnen und zur Erstellung von Graphiken. Ähnlich S oder S-plus (läßt den meisten S-Code unverändert laufen). Verfügbar für Windows, verschiedene Unix-Flavors  (einschließlich Linux), NextStep und Mac. Bietet eine breite Vielzahl der statistischen (lineares und nichtlineares Modellieren, klassische statistische Tests, Zeitreihenanalyse, Klassifikation, Sampling...) und graphischen Techniken und ist leicht erweiterbar. Gut entworfene Publikationsreife Graphiken können produziert werden, einschließlich der mathematischen Symbole und der Formeln.

gretl: Gnu Regression, Econometrics and Time-series Library, ist ein Cross-platform Softwarepaket für ökonometrische Analyse, geschrieben in der Programmiersprache C. Veröffentlicht unter der Gnu GPL Lizenz.
Features:

• Easy intuitive interface (now in French, Italian, Spanish and Polish as well as English)
• A wide variety of least-squares based estimators, including two-stage least squares and nonlinear least squares
• Single commands to launch things like augmented Dickey-Fuller test, Chow test for structural stability, Vector Autoregressions, ARMA estimation
• Output models as LaTeX files, in tabular or equation format
• Integrated scripting language: enter commands either via the gui or via script
• Command loop structure for Monte Carlo simulations and iterative estimation procedures
• GUI controller for fine-tuning Gnuplot graphs
• Link to GNU R for further data analysis

WinIDAMS, ein von der UNESCO kostenlos erhältliches generelles Statistikpaket.
WinIDAMS is a software package for the validation, manipulation and statistical analysis of data, developed by the UNESCO Secretariat in co-operation with experts from various countries. It is distributed free-of-charge upon request.

Octave: a high-level mathematical programming language (free MATLAB clone) for numerical computations -- solving common numerical linear algebra problems, finding the roots of nonlinear equations, integrating ordinary functions, manipulating polynomials, and integrating ordinary differential and differential-algebraic equations. It is easily extensible and customizable via user-defined functions written in Matlab syntax, or using dynamically loaded modules written in C++, C, Fortran, or other languages. Available for Linux/Unix and Windows.

Free statistical Matlab scripts: these m-files by the University of Bern run on MATLAB (and may also run on Octave with minor modifications, not tested)

Scilab: a scientific software package for numerical computations in a user-friendly environment. Available for Windows, Mac and Unix computers, this is a sophisticated programming language with a MatLab-like syntax, hundreds of built-in functions and libraries, 3-d graphics, and symbolic capabilities through a Maple interface.

Calcugator:
The Calcugator is a calculator, a plotting engine, and a programming environment. It's also a computer program you may download and use for free. An online applet with a restricted user interface is available too.

1. As a calculator it excels in simplicity of use and rivals programs like MATLAB. It is equally suited for engineers as well as for high school students. It offers close to 200 functions/operators to perform real, integer, rational, complex, boolean, statistical, vector, array and matrix computations. Both the input and output of the program are displayed on standard windows which can be further edited, saved, merged, print-previewed and printed.
2. As a plotting engine it allows rapid creation of 2D plots of functions as well as polar and parametric displays. It also allows creating 3D plots of functions, contour plots and 3D parametric displays. The Calcugator has also functions to create bar, pie, pareto and xy charts. All plots can be configured using the mouse (zooming, panning, selecting). Titles and labels are supported. However, the most useful characteristic is that all figures created by the Calcugator can be exported into popular file formats or pasted into an editable window.
3. As a programming environment it offers a computer language with similar syntax as that of Java/C/C++. However, the user does not need to compile his/her programs. The language is simple, compact and the error control is intelligent when displaying messages. The creation of user-defined functions is natural and mimics the syntax used by a teacher on the blackboard.

PSPP, a free SPSS clone, GNU project in alpha state. PSPP is a program for statistical analysis of sampled data. It interprets commands in the SPSS language and produces tabular output in ASCII, HTML, or PostScript format. The name PSPP is not intended as an acronym, but it is easy to invent expansions for it. In previous releases, PSPP was known as Fiasco. This web page corresponds to PSPP version 0.2.0. PSPP development is ongoing. It already supports a large subset of SPSS's transformation language. Its statistical procedure support is limited but growing. A manual is available.

For more free packages, please see our [ Free Statistical Software ]page