The Zin Obelisk is an intriguing, entertaining, sometimes frustration activity with wide use in team development and communications settings. I've used it myself frequently with group of up to eight people as it quickly and accurately reveals how people choose to contribute and participate within teams and small groups.

Up to now I've always used the version in the excellent 'Team Development Manual' published by Gower, but a TrainingZone member has dug out a version available for download from the Web with complete instructions and explanation.

If you've not used it before, it's definitely recommended!