Hi I found this site http://happy-neuron.com/

It has some free tests that stretch and analyse your mind. It has a one week free trial.

When I tried the memory tests I got 50% of what my wife got - not heard the end of it yet.

The one that really threw me was the test where you have to identify a series of pictures of hands - and whether it is a left or right had. There are no intense pictures or sounds just simple photographs of hands in different positions- sounds simple? I did the test once and it overloaded my brain so much it took me 5 hours to recover.