GNU General Public License (GPL)
Yes
NITRC
PsychoPy
FreeBSD, MacOS, Linux, Windows
Python
PsychoPy - Psychology software in Python. PsychoPy is an open-source application to allow the presentation of stimuli and collection of data for a wide range of neuroscience, psychology and psychophysics experiments. It is intended as a free, powerful alternative to Presentation or e-Prime.
PsychoPy
Console (Text Based), Win32 (MS Windows), English, Beta, FreeBSD, GNU General Public License (GPL), Experimental Control, Python, Developers, End Users, MacOS, Linux, Windows
http://www.nitrc.org/projects/psychopy/, http://www.psychopy.org