I learned about dual n-back tasks the other day which have been shown to increase fluid intelligence (gF).
This site describes it well, and has an entry level test (only dual tests increase IQ):
This site is the best online site (close to the original protocol):
If you read the study, it’s interesting to note that it doesn’t matter how high you N value is.
I’d like to add that we’ve recently made the soakyourhead.com source code freely available as well. If you’d like to take a look, it’s at: http://www.soakyourhead.com/dual-n-back-open-source.aspx .
PyQ is a free open-source Python implementation of the Dual N-Back exercise. PyQ includes an optional Triple N-Back mode that introduces differently colored squares as a third stimulus.
PyQ will run on Windows, Mac OS X and Linux.
Get it here: