Dynamics 2.
An excellent program for dynamical systems analysis. Runs on MS-DOS and UNIX platforms.
We have a few copies here at CNS. The usage of the program is somewhat restricted though.
Chaos Classes.
A collection of C++ Classes for a dynamical systems analysis, written by
David Sweet.
If you want to do your numerical calculations using C++ this is a good place to start from.
Chaos Classes are free like a free speech.
Math::ODE.
Runge-Kutta numerical integrator written in Perl by
Jonathan Leto. Comes with documentation and examples
for usage. This package is free software; you can redistribute it and/or
modify it under the same terms as Perl itself.