This is a classic, and a wonderful “sucker” effect – they think they know what you are doing, but it turns out they are wrong!
Place a hat or other container on the table. Show a solid wooden die and a handsome box with two compartments and four doors. With all doors open, the die is placed into the left compartment. The doors are closed. The box is tilted to one side, and the audience can hear the die sliding into the right compartment. You tell them that the die has “disappeared” and open the left hand door to “prove” it. Of course, they tell you that the die was just slid over into the other compartment.
So you close the door, tilt the box so the audience hears the die slide to the left compartment, and again declare that the die has “disappeared”, opening the right side door this time. The audience tells you that the die has just slid over to the left. So this time, you open the right side AND the left side doors – the die has indeed vanished! And you produce the die from the hat that was sitting on your table all along.
Double-door method die box. About 8″x4″x4″. Sturdily made and beautifully finished in high gloss lacquer paint.