Brain Teasers
- 41
- Amos Storkey - Visual Illusion of the Month
- Collection of illusions and images chosen for novelty and distinction from the usual set found in most collections.
- 43
- Cool Optical Illusions
- A growing collection of optical illusions and eye tricks, including original illusion pictures and a collection of optical illusion desktop wallpaper.
- 44
- Cut the knot: Visual Illusions
- A collection of about 20 illusions - all accompanied by Java applets. Interactively changeable attributes help investigate which ones are in fact responsible for tricking the brain.
- 46
- Mchael Bach: Optical Illusions & Visual Phenomena
- The stress here is on relative novelty and interactivity, in combination with a scientific background. Regularly updated.
- 52
- Skytopia - Dynamic Optical Illusions
- A selection of old, new and original optical illusions. Many pictures are enhanced via the use of 3D and animation.
- 55
- BrainDen.com: Brain Teasers and Riddles
- Classic puzzles and riddles sorted in several sections - general logic, weighing puzzles, Einstein's riddles, number sequences, and crossing river.
- 56
- Braingle's Riddles
- Contains thousands of popular riddles, as well as user submitted and rated riddles.
- 57
- Historiddle
- Collection of free internet puzzles, riddles and brain teasers based on the history of the 20th century.