Clink. Clank. Clink.

That’s the sound of coins dropping into the tzedakah box, the charity receptacle once found in nearly every Jewish home. Getzy Fellig of San Francisco has re-created an electronic version of the tzedakah box — for desktop, laptop and tablet computers as well as smartphones. When you use it to donate to a synagogue or other nonprofit organization, you even hear that familiar “clink.”

Fellig’s 2-year-old company, Nadanu Technologies, takes its name from the ancient Sumero-Akkadian word for “giving,” and the firm’s logo is the cuneiform symbol for the word. “In this age of online payments and cellphone payments, when it comes to religious organizations, something about the actual physical act of charitable giving has died,” Fellig said. “When you just fill out a form on your computer, part of the concept is lost.”

Fellig, 27, added, “In Jewish mysticism, that satisfying ‘clink’ when coins are dropped into a charity box is said to help battle the evil forces of the world. That concept gave birth to Nadanu, where we provide people the opportunity to donate online without losing the significance of making a physical donation to a charity box or offering plate.”

Getzy Fellig

For the past three months, Rabbi Yaakov Kagan, spiritual leader of Chabad of Contra Costa in Walnut Creek, has recommended that donors use the virtual charity box:

http://www.mycharitybox.com

“It’s going great — the ease of going from brick to click is spontaneous,” he said. “The novelty encourages people to interact in an old-fashioned way and yet with a friendly, high-tech way as well.”

Kagan said he has noticed that once individuals are familiar with the virtual charity box, they donate more often. “Once they start interacting with the site, they tend to think about you and your organization more often. Plus, dollar for dollar, this is one of the best ways to turn someone’s wish into a gift without it costing as much on the processing side.”

Signing up is free. Nadanu charges 3.5 percent of all transactions plus a 25-cent fee per transaction to cover costs — and add a “clink” to Nadanu’s revenue.

Fellig lives near Fisherman’s Wharf with his wife and three children. He moved his company to San Francisco from New York in February. Because he is new to the area, Nadanu so far works with only 12 Bay Area companies. Among Nadanu’s other 1,200 customers are the Jewish National Fund of Canada, the Jewish Federation of Cleveland, Yeshiva Noam of New Jersey, numerous Christian churches, the March of Dimes and the Salvation Army, which uses a virtual image of its familiar red Christmas collection kettle.

Nadanu’s mission is “to unite all people regardless of faith, creed and belief into a powerful force for making the world a better place for all.” In addition to helping make donating easy, Nadanu provides marketing tools for clients.

It all works for Rabbi Peretz Mochkin, head of the not-for-profit Friendship Circle, based in Palo Alto. “When I saw that Nadanu had created a virtual charity box, I was one of the first to sign up,” Mochkin said. “I’ve even recommended the service to other organizations.”

Fellig grew up in Miami, where his father is a Chabad rabbi. “I have been in a nonprofit environment all my life. It wasn’t just a doctrine of our religion, but it is the way my father is able to do what he does,” said Fellig. Entrepreneurial by nature, he left a yeshiva program at 16 and quickly became involved with some startup companies. Later, he had “some successful stints in real estate development and commodities trading.”

Seven years ago, Fellig entered the tech world. In 2009, he co-founded Nadanu with Chaim Sztabzyb, the company’s chief technology officer. The two have been friends for 15 years. “I had the vision, and Chaim had the expertise,” Fellig said. “We moved here to expand the company, and we are excited about where Nadanu is going.”

What does Fellig tell those leery of technology?

“Saying that you don’t collect donations electronically is a totally unrealistic statement,” Fellig said. “Nobody takes surveys in synagogues to find out how many people use computers or phones to donate — but even if only one in five congregants uses these systems, then the synagogue should be there for them.”