Many people would be willing to donate a quarter for wildlife conservation, reckoned Norman Gershenz, a conservation biologist at San Francisco State University.

Gershenz talked his friend at the San Francisco Meter Authority into donating the department's retired parking meters. Then he had a design company retrofit them with a colorful hummingbird or jaguar cutout that pops up in the window when a quarter is deposited, along with a message saying, 90 square feet of rainforest has just been saved.

When a prototype was installed at the San Francisco Zoo, it raised $1,200 in donations the first week. The idea has since spread to zoos, botanical gardens, museums and nature centers around the U.S. Already, the meters have collected more than $1 million for habitat conservation.

Norman Gershenz, Center for Ecosystem Survival, San Francisco State University Department of Biology, SF, Calif., 415-338-3393.