Purpose
Knowing when to stop making definitions.
How it is done
Half of your players stand in a circle, the other half stands in the middle with eyes closed. Choose an arbitrary location, e.g. a bank.
Each outer player adds an element of his picture of the location to the shared picture. E.g. "expensive wall-to-wall-carpet", "clerks in stiff suits", "a poster which advertises a savings plan", "potted plants in hydroculture", "a bank-robber with a mask".
The inner players give feedback. They have gestures for:
Enough: I have a complete mental picture of the place.
Irrelevant: This feature did not contribute anything.
Contradiction: This feature does not fit into my mental image (e.g. the mental image was that of a sleepy, boring day at the small-town bank, and the bank-robber just does not fit in).
(from a workshop by Gunter Loesel)