COGENT: Cognitive Objects within a Graphical EnviroNmenT
COGENT is
a really nice project that uses a graphical environment for cognitive modelling. It's GNU licensed and the developers provide binary installers for Windows, Linux and Mac OSX. In the backend they use
SWI Prolog
to do the modelling. The user can do most of the modelling via visual programming and the UNIX/OSX version is scriptable.
The book
Modelling High-Level Cognitive Processes
by Richard P. Cooper utilizes the
COGENT
environment for it's examples.