This web page takes advantage of a little-known feature in the latest version of Internet Explorer which allows applets to determine where on the screen your eye is currently focused using infrared signals from the monitor which bounce off the eye and are subsequently detected by the CPU. By monitoring the current eye focus position, the software is able to place black dots only on locations which you're not currently looking at. With practice, you can defeat this by changing eye position very quickly. Try to confuse the software by starting to move your eyes in one direction, then quickly switch to moving in a different direction at a right angle to the first direction. If you do it just right you will be able to see the black dot clearly before it is erased. If not, just keep practicing for several hours - eventually something will happen.
Jim... I'm shocked and appalled at your cruelty. My optometrist thanks you, however. P.S. I'm typing this with my eyes closed as I am no longer able to focus on a computer screen. Guess I'll have to switch to brain surgery, as I can't see good anymore.
Anxiety does not empty tomorrow of its sorrows, but only empties today of its strength. – Charles Spurgeon