The Psychology Experiment Building Language (PEBL) is a free cross-platform system for designing and running computer-based experiments and tests. It is free to use, free to change, and free to give to others. You will always have access to the software you used to collect your data, because there are no licenses to maintain, and you can give your experiments to others and they will be able to use them, even without buying a license.
PEBL experiments are creating with a special-purpose programming language designed to focus on the critical aspects of creating experiments. These include easily creating displays (graphics, shapes, text, etc.), collecting responses (mouse and keyboard), experimental design (randomization and counterbalancing), and data recording.
PEBL Test Battery
PEBL distributes a set of approximately 50 standard and novel test in the form of the PEBL Test Battery. Many of these tests are the only free version of commonly-used tests that otherwise cost hundreds of dollars.
References and Citations
If you use PEBL in your own experiments, please reference it. A proper citation for the software is:
Mueller, S. T. (2010). The Psychology Experiment Building Language, Version 0.11. Retrieved August 2010 from http://pebl.sourceforge.net.
I have also published a refereed article in which I discuss PEBL and some of the tests. This is also a suitable reference to use:
Mueller, S. T. (2010). A partial implementation of the BICA cognitive decathlon using the Psychology Experiment Building Language (PEBL). International Journal of Machine Consciousness, 2, 273-288. For more information, see the PEBL Cognitive Decathlon.
Finally, Brian Piper has published a norming study on several of the PEBL Test Battery tests:
Piper, B. J., Li, V., Eiwaz, M. A., Kobel, Y. V., Benice, T. S., Chu, A. M., Olsen, R. H. J., et al. (2011). Executive function on the Psychology Experiment Building Language tests. Behavior Research Methods. doi:10.3758/s13428-011-0096-6 http://www.springerlink.com/content/ph08767120x54823/
A number of research papers that have used PEBL have been published and are identified here.
A tutorial held at Cognitive Science 2011.