Icebreaker exercise: Ask participants if they are half-full or half-empty about a specific prompt. For example, half-full or half-empty about buying candy from a vending machine on your hotel floor at 11 PM? You can prompt meeting attendees to sort into five groups by physically moving to a location: Empty, half-empty, half-full, full, or no opinion. Ask ten to twelve questions and the people in the room are almost certain to find themselves mixing and matching with other participants.