Puzzles, etc...
Cut The Knot
Puzzles
The professor and company...
The missing square
Strange dissection
Dichotomy Island
The light bulbs
A little arithmetic
The 12 snooker balls
Bruler des ficelles
Chapeaux noirs et blancs
9 people
Optical illusions
Count the black dots
Are the lines horizontal? Are they even lines?
Flower power
Spiral?
Moving spirals
A weird "rotating" picture
Strange
perspective