Do you have an intuitive sense for numbers? This site, based at Harvard University, includes a test for your intuitive rather than analytical ability around numbers. This and the other tests on this site are on-line science experiments into the brain so by taking part you are helping increase our understanding of how we function. Other tests include short-term memory, group membership and facial recognition (which apparentlly peaks around 30 years of age). http://www.testmybrain.org/

How happy are you? Positive psychology is having a big impact on work practices and life generally. If you want to know how happy you are, and what factors contribute to your happiness, take this 1 minute test at: http://news.bbc.co.uk/1/hi/programmes/happiness_formula/4785402.stm

Gorillas you have missed! You've probably heard about the student in the gorilla costume who wanders amongst people passing a basketball - and yet nobody notices it. You can watch it (providing you have Quicktime - free from Apple for all platforms) at: http://viscog.beckman.uiuc.edu/djs_lab/demos.html.

What sex is your brain? If you've ever wondered whether you think like a man or a woman or how male or female your brain is, try this test at: http://www.bbc.co.uk/science/humanbody/sex/add_user.shtml

How prejudiced are you? Researchers at Harvard have created a test which suggests that even the most well-meaning of us have hidden prejudices. Try the Implicit Association Test at: https://implicit.harvard.edu/implicit/

Body Language Just how good are you at detecting fake smiles. You never know when this might be useful. Try your skill at judging fake smiles at: http://www.bbc.co.uk/science/humanbody/mind/surveys/smiles/index.shtml

Derren Brown's Mind Control website is an entertaining source of exercises and insights into psychology and Neuro-Linguistic Programming. http://www.channel4.com/entertainment/tv/microsites/M/mindcontrol/index.html