And one of my favorites, the Volkswagen fun theory, inspired some positive social re-engineering by using play as the motivator to behavior change.

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His theory was that by letting them see the fun side of the iPad, they would get attached.

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Mersenne primes are most relevant to number theory, but most participants join Gimps for the fun of having a role in real research - and the chance of finding a new Mersenne prime.

BBC: NEWS | Science/Nature | Largest Prime Number discovered