The Box of Memories
A volunteer picks one of 4 wooden cards and secretly chooses of one of the 8 possible memories on the card.
After checking the 3 other cards to see if the chosen memory is on them and discarding the cards that do not have the memory you have the volunteer constraint on that memory while touching the cards. Without the volunteer saying a single word at any time you are able to tell them exactly what memory they are thinking of.
There are 15 different memories that can be freely chosen.
The lid of the box has a very easy to use crib sheet that can be displayed in plain site because it appears to be a series of mystic circles and odd symbols.
You only need to see the backs of the wooden cards in play or discarded to know what the memory is.
The volunteer does not need to say anything or write anything down.
Easy to do.