Indiscriminate spitting on walls and corners of buildings is a perennial problem, a serious hazard to public hygiene.
A social service campaign was undertaken to stem this rut - full length mirrors were put up in office buildings and other public places with a message that encouraged the 'spitters' to spit on themselves.
It played on the ego of the ‘spitter’ as spitting on a person is considered the worst form of insult. Proved extremely effective. Drastically reduced the menace, with very visible results.
In fact, it worked better than putting pictures of gods to curb spitting.