Hi, I thought you may like this Mentalrobics exercise from Braingle.com:
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Brainstorming

A brainstorm is a meeting where you try to find solutions to a problem. They are frequently conducted in groups in order to get a variety of different perspectives and ideas. To have the best chance at getting different perspectives, choose participants with a range of different backgrounds for the brainstorm (i.e. don't pick all engineers to solve an engineering problem).

Every brainstorm should have a moderator whose job it is to write down all the ideas and keep the brainstorm on track. Make sure that everyone can see all the ideas as they are written (use a chalkboard or something similar).

To keep the energy of the meeting high, limit each brainstorm to 30 minutes (even if you don't have a solution by the end of the meeting) and have plenty of cookies, soda, pens, and paper available.
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For more mind exercises: http://www.braingle.com/mind/