How do they do this?

[Gujar]

http://www.milaadesign.com/wizardy.html

How the hell does this work?

[Mercenary]

looks like Jinn's are making websites too! That's really spooky but there must be some trick to it

It works even if you dont stare at the screen!!

[entralinks]

Adding the digits of a two digit number and then subtracting them from it always gives the answer that is a multiple of 9.

Now when you see that chart with a lot of symbols, all the multiples of 9 will have the same symbol with them. For every new game the system randomly chooses a certain symbol to show for the multiples of 9. Now because your answer had come to be a multiple of nine, no matter which multiple of 9 it was, the system already knows it has to show the same symbol to you as your guess which it had chosen just before for the multiples of 9.

[Mercenary]

Right, it randomly changes the symbol for each game to make it look like you're picking different symbols.

I remember a similar one a few years ago.

[Mercenary]

Why did you have to kill the magic Entra? It's Xmas you know!

[entralinks]

You remember my review on King Kong movie? I wrote the whole story with detailed scenes and ending and spoiled it for many who hadn't seen it. But this one's right up there too.

[the true passionist]

Adding the digits of a two digit number and then subtracting them from it always gives the answer that is a multiple of 9.

Now when you see that chart with a lot of symbols, all the multiples of 9 will have the same symbol with them. For every new game the system randomly chooses a certain symbol to show for the multiples of 9. Now because your answer had come to be a multiple of nine, no matter which multiple of 9 it was, the system already knows it has to show the same symbol to you as your guess which it had chosen just before for the multiples of 9.
:14:

[Mercenary]

You're the sort of person who would be the first in line to watch a mystery movie on the morning of it's release and then spend the rest of the day/week/month or year visiting cinema's and shouting out the ending to everyone waiting to watch the movie!!

Come on admit it, you've done that havent you?

[Gujar]

The triangle one is also a dud. Check the gradients of the smaller red and orange triangles in the last image. They aren't the same.

[HoMeR]

nice, lol

[iZeeshan]

I figured out the trick but seems like Entra already spilled the beans.

[entralinks]

You're the sort of person who would be the first in line to watch a mystery movie on the morning of it's release and then spend the rest of the day/week/month or year visiting cinema's and shouting out the ending to everyone waiting to watch the movie!!

Come on admit it, you've done that havent you?I've done that even without watching the movie man.

[entralinks]

I think I read or heard this in news somewhere, someone actually did this for the last Star Wars movie I think.