Does anyone know if any interactive media has have any magic tricks in them? By magic trix I mean stuff like guessing what card the user is thinking about. I know a couple of tricks that could be done with software but I have not seen much implemented. The ones I have seen so far was a sprite (or some other brand perhaps ) mindreader, a guess the card html trick and the usual "spam" mail where you should think of a word. If anyone has any ideas of tricks that could be done or know any software that has any magic trix I am very interested in hearing about this. edit: spelling.

Hmmm... other than the aforementioned card guessing games (more of a test for divination or ESP), i can't really think of many practical or interesting tests/tricks that have been implemented (or could be implemented?) on a PC.

I'm rather curious, do you intend to make a game based on magic tricks applied to the PC? Or is there some other reason?

What I wanna do is to make a game that messes with the player's head. To do this I planned on using a mixture of psychology, magic tricks and illusions. I have just begun thinking about this and wondered what kinda of Interactive media that did something like this allready exisited.

Just started reading a little on hypnosis to see if anything like that could be useful for my eveil plans :P

The one that I know that messes the most with the player's head is eternal darkness. Just for the beginning of the game tought.

Your character has a sanity meter, the more monsters he fight the more insane he becomes. When your character has it's sanity low, funny stuff happens.

You open the door. There is no one behind it. You enter the room. When you are in the middle of the room, monsters come from the windows, from the room, from stairs, from the same door you came from.. and off you go to wack the monsters with your pistol. When you have beaten half of the monsters, suddently your controls don't respond! an error message appears on the screen saying "input error, please check that your controller is properly connected" you rush to the gamecube and disconnect the controller and plug it back... nothing changes! you do it again and again.. still nothing! and well... your character is dead... monster food.

A flash is shown on the screen, and again it presents your character before opening that door. He screams "I'm becoming insane!". Everything is just as it was before crossing the door.

That's the most I have seen about messing with the player's head. There are lots of things that you could do, but please don't over do it, we don't want crazy people coz of a videogame :p

Eternal Darkness seem to have alot of cool stuff in, read about the insanity effects in some faq. Might buy a gamecube just to playt (they are pretty cheap now). Will also be fun to see what kinda effects call of cthulhu will have.

The effects I am thinking about though is not the computer fooling the player, but rather the player fooling him/herself ( I mean it is no problem for a program to change the number of some virtual card).

Derren Brown has some pretty cool tricks that he says are based on psycholgy and allthough I know there are alot of standard magic tricks behind alot of his tricks, he does do some cool stuff that might be possible to do in a game.

It is strange if noone has tried todo something like that. There must be a paper or something out there.

Not really a trick, but Black&White had a cool effect in it. Part way through the game, the computer starts whispering your name to you. The whisper is very subtle, but when you realise its you the computer is talking to, its quite freaky.

The first time i heard it I though that was a great effect because I couldn't understand how the computer knew what my name was. Then I remembered that i typed it in at the being of the game, doh. I also found an MP3 file with the same voice whispering about 100 different in the game folder, so it was obviously just referencing what i typed in to a certain time in the sound file.

Simple, but effective.

Love that name whispering trick!

Otherwise a lot of those "I am reading your mind" tricks are feasible. Honestly. I remember once, there was this trick David Copperfield was doing on TV, it was the Orient Express or something. You had 9 rooms (3 by 3) and you started wherever you wanted, and the trick was that David would tell you to move by so many squares (can't move to the same room twice, can't move diagonally) then eliminate squares from the map, showing that you weren't there. Then you would finally end up in the one square he wanted you to be.

Another trick that would seem quite different but is in fact using a similar tactic is the one where you have say, 5 cards from a card game (only Kings Queens and Jacks), and you choose one, any one! Now mix them them, put them back on the table and hey presto! your card is gone! How come?
Simply put, ALL the cards have changed, but because they all looked very similar and consequently, you were focusing on remembering yours, when ALL change, you don't notice it: you just notice yours is gone.

What's the connection between both tricks?
One, it doesn't matter what you choose, what matters is where you end.
The whole trick is geared to make you think your choice matters, especially in the case of David Copperfields trick. But what he does is herd you towards a given point.
Then gives you the "Shazaam!"
In the case of David Copperfield's trick, it's very straightforward, because it's just a sort of chess puzzle, with your king trying to escape and survive as long as possible, but always ending where the "magician" wants it to.

The card trick uses the same general concept : keep the player busy thinking about himself so he doesn't notice the overall changes that would tell him clearly what's going on.
It's all about inducing tunnel vision, if you will. Magicians have a specific term for that, but I forget it. Misdirection, I think?

I also remember a cool trick Derren Brown did once on TV. He was trying to "plant" a card in someone's mind by talking to them. The "trick" (this one was easy to figure out), was that while talking and telling them to "visualise" the card he would make lots of gestures with his hands, constantly, but discreetly, using some that would hint at the suit then at the number of the card.
For instance, he would point to his heart, or hold both his hands on his chest, for Heart. Or he would join his hands like in a prayer, or put his index against his thumb, pointing upwards, to indicate Spades. Diamond would be both hands joined with the indexes upwards and thumbs downards, showing a big losange. Clubs would be circles.
This is similar to tactics you could use while cheating at cards, to indicate a suit to a partner (Maybe you know of Marcel Pagnol's famous quote from his book Marius : « Tu me fends le coeur, j'ai le coeur fendu.... ») but reverse engineered, if you will.
Of course, the person on the other end _knew_ they had to guess a card so they were, possibly incousciously, trying to read anything he would say/do, which made his work easy IMO.
Also the fact that he was choosing the card himself meant he would deal with cards that were easy enough to gesture without looking odd.
Showing a ten by flashing both your hands with fingers outstretched is easy enough, I can even see how to show a J to the person, but how to indicate a Queen ?

Anyway, like I said, some of those tricks are easy enough to understand when you get the main idea behind them...

Would it be possible to do anything other than mind reading tricks? Could the mouse or some other input device be used? The problem is that the user excecpts the computer to cheat so you have have some situatuion where the user thinks he/she as control over something. Reading the mind is quite nice. What other methods might there be?

well, like I said, it's not really mind reading, it's more "mind herding", or mind control if you will, but always making the player think he is in control.

You could try to do some trend reading, pattern matching sort of thing. A bit like Amazon will recommend books on those you have bought, and other people have bought. That's more AI, actually. Trying to see tendencies in a player.
Maybe you could do it in a subtle way by having choices that don't look significant to the player when he does them, but when you add them up all together, it paints a useful picture for you to then add elements in the game.
Think of it as giving the player a personality test, but instead of clearly saying so, asking a question at a time, do this in the game. Instead of asking "what's your favourite colour" to the player, give him several objects to pick from with _absolutely_ the same benefits, but only the colour differs (say, your light saber colour, in Star Wars).
A bit like, in a roleplaying game, your dialogue choices will influence your alignement. Well you could add more dialogue options that are not really influential in the discussion, but add "personality" to the character, and allow you to pick up more clues about the player (not the character) that you can later reuse.
I'd say reading up on psychology might help, there.

ahw: good suggestions!