A clever little trick to be performed with a single dice.  This trick uses the old principal of progressive elimination to produce it's mystic effect.

Your subject rolls a single die with your head turned or blindfolded so you cannot see it. They then place the die under your cupped hands. Now you ask your subject to think of a number from 1 to 6 without telling you what it is. The nature of a cube means that only three faces of a die may be seen at one time, so position the die at the right angle for your subject to see them,. Now lift your cupped hands and ask your subject if they can see their number. Then turn the die. If you have a good sense of spatial awareness you can turn the die in such a way so that a different set of dice values are shown to your subject. Again, lift your cupped hands and ask your subject if they can see their number. Finally, you may have to turn the die once more, raise your cupped hands and ask if they now see their number. Now astound your audience and subject by turning the die, with their number face-up and mystically announcing it.

If you think about it, you can work out which number your subject has thought of by asking whether they see their number no more than three times. The first question will eliminate three possible faces of the die: if they do see their number, you know it can't be one of the three faces of the possible six, they can't see. If they don't see it, you know it can't be one of the three faces they do see. If they do see their number, you must then turn the die so two of its faces are kept in view but keeping track of the position of the third face. If the subject doesn't see their number when before they did, you know it must be the third face without asking any further questions. If he does see his number you know it must be one of the two, making it a simple matter of turning the die once more, so one of the two faces is hidden from view, allowing you to know which number it is.