Before you get into the tutorials, here are some images that are guaranteed to send you reeling . . .

WARNING ! . . . . Do not view these images if you are on strong medication, or if you have consumed more than 2.8 litres of full strength beer within the last 20 minutes.

No.1 It appears that this brick wall is very hot. Would you not agree?

No.2 Is this a real spiral, or concentric circles? It's really just concentric circles.
This illusion is so powerful, it can even cause your finger to trace in a spiral.

No.3 Here vertical or horizontal edges seem to appear distorted. Other areas seem to move.

No. 4 The lines look as though they are tilting, but are parallel.

No. 5 These circles seem to cross over one another, but your wrong!

No. 6 The vertical lines appear to be bent, but they are parallel.

No. 7 Watch how the intersections in this image scintillate and move about.

No. 8 Can you see the grey angled bars move from side to side?

No. 9 Which of the brown bars is longer? They are both the same.

No. 10 red appears to be magenta or is it orange?

No. 11 Is the grey surround in this image lighter than the centre square?

No. 12 Are all the vertical lines the same length?

No. 13 Stare at the centre, are the blue
rings rotating? Which direction are they going, clockwise or anti clockwise?

No. 14 Watch this image as you move your head closer and away. It should rotate.

No. 15 Got the wobbles.

No. 16 Animation where there is none. Turns from left to right.