Since 850 AD in Indonesia, the local currency, the Rupiah, has been issued along with another currency, the Narayan Banjar (which means "working for the good of the community"). This currency is measured in time and can only be earned by giving cultural or artistic performances - and the currency can only be spent by attending a cultural or artistic performance. Between 50 to 500 families from the community use the Banjar.
A Banjar unit equates to approximately 3 hours. When the community needs to organize a festival or build a school - two budgets are planned: one for national currency and the other for "time-currency". The poorest people in the village have the option to invest more time on the project and use less money - while group members who are financially better off - will inject more money.
The Banjar Narayan is an innovative way to capitalize on what poor communities have most: time, and a lack of Rupiah.
This form of cooperation between individuals and the dual currency system - is the fabric of Balinese society. Residents participate on an equal footing in the financing of joint projects and, as long as it does not harm their community, they may finance projects in other communities. This alternative to the "classical" definition of money has made it possible for community to develop culture and arts throughout the country.
There are approximately 2500 examples of "similar" currencies systems that have been created and used for social purposes.