He lent $27 of his own money to 42 villagers and built a bank around it

In 1976, economist Muhammad Yunus lent $27 to a group of stool-makers in Bangladesh who couldn't get credit from traditional banks. The experiment grew into Grameen Bank, which lends mainly to poor women with no collateral required, using peer accountability instead. Yunus and the bank shared the 2006 Nobel Peace Prize.

— Wikipedia contributors, Grameen Bank — Founded 1983, building on 1976 pilot