This sign was in a public toilet, by the urinals. Translated with a small amount of poetic licence, it reads "One small step (forward) for a man, one giant leap for civilisation." Public service announcements encouraging 文明, or 'civilised', behaviour are actually quite common, particularly on buses and the subway. Whether this is: A) a symptom of continuing insecurity at how civilised China really is, having thought itself the only civilisation in existence for so long before a rude awakening in the 19th and 20th centuries that almost tore it apart; B) a reflection of how the Chinese idea of 'civilisation' was always associated with the elite, and that bringing average people up to civilised norms is a sign of China's continuing development; or C) representative of the fact that the term can simply be used in a broader way that its English equivalent, I'm not entirely sure. All I know is that the sign wasn't working. That place stank like - well, it stank like a Chinese public toilet, no simile necessary.