Couple of Tests
The Gender tests claims 100% accuracy:

<a href="http://test.thespark.com/gendertest/" target="_blank">http://test.thespark.com/gendertest/</a>

I Must say it picked my Gender Correctly.

The other a game but nonetheless-The Death Test(on what date will you die?):

<a href="http://test.thespark.com/deathtest/" target="_blank">http://test.thespark.com/deathtest/</a>

September 10, 2037
24% chance its a Heart Attack