This is without a doubt one of the coolest PC-Illusion's I have seen so far.
Follow the instructions:
1) Relax and concentrate on the 4 small dots in the middle of the picture for about 30-40 seconds.
2) Then, take a look at a wall near you ( any smooth, single coloured surface )
3) You will see a circle of light developing
4) Start blinking your eyes a couple of times and you will see a figure emerging...
5) What do you see? Who do you see?