The following is Al Koran's basic handling of the "Note Under Cup" or "Three Cup and Note Routine." It was one of Koran's favorite impromptu effects. Borrow three cups from your host. You need to locate one cup with a small imperfection. This can be a small crack, chip, blemish or discoloration, a slightly off-center trade marking, etc. You shouldn't have too much trouble locating one odd cup in three. The three cups are placed in a row, we'll call them "A," "B," and "C." THE LETTERS ARE FOR YOUR REFERENCE ONLY. For the sake of simplicity, we'll make "A" the marked cup. Have a spectator place a crumpled-up bill (one dollar bill, five pound note, etc.) underneath one of the cups and exchange the other two. For example, if the bill is under placed under "B." He should switch "A" and "C." If under "C," then "A" and "B" should be transposed, etc. Note the position of "A" and ask this to be done as you turn your back. When you turn back around, have the spectator who placed the bill under the cup, hold your wrist as you pass your hand back and forth over the cups without touching them. After a few contrived pauses, your hand comes to rest over the cup with the bill underneath. As you may have guessed, the method is simply a case of elimination. If "A" is in the same spot, you know the bill is under it - since it hasn't been moved. If "A" appears at the "B" spot, you know the bill is under (position) "C" and likewise, if "A" is at the "C" spot - you know it's under (position) "B." For a finish Maurice Fogel recommended revealing the serial number on the bill - a relatively easy matter if you switch in your duplicate bill (or other currency note) for the borrowed one before the effect begins. This can be done quite casually in the course of setting up the cups, since no one is expecting a switch of the bill.

Tip: This same principle can be applied to bottle caps that bear a "date stamp" or some other marking by the manufacturer on the side (fairly common these days). Just locate one cap in which this ink stamping is slightly askew when compared with the other two, so it is easily spotted at a glance. Of course, instead of a crumpled up bill, just use a coin underneath!