One woman''s experiment to understand how the power of giving without reward can change lives.Random acts of kindness campaigns are increasingly popular as we look to kindness to strangers as a means to create a kinder and more caring society. For 14 days, Dr Sandi Mann, from the University of Central Lancashire, carried out her own ''paying itforward'' challenge, handing out free chocolate, coffee, umbrellas and more in the hope that her generosity would inspire others to carry forward more random acts of kindness. The results surprised her.