Propaganda slogans on walls of buildings

Asia Times Online :: China News - The writing is on the wall:
"" "Mao had revolutionary slogans painted on walls, and billboards were used to promote the party's line and policy, just like outdoor advertising for commodities. Under Mao, both in the civil war leading up to the taking of power and afterward, outdoor slogans were a highly effective propaganda instrument.

In the Mao era, the use of outdoor slogans reached its climax"........

Nevertheless, one of Mao's legacies is that outdoor slogans are still widely used as propaganda tools, though most prime outdoor space in large cities has been sold for revenue-generating advertising. For the political messages, the difference nowadays is that the slogans are much more diversified and largely address local affairs. "

This might be a good idea for Second Life.