Winner Forrest Hanson and family
Courtesy Forrest Hanson/Twitter
05/27/2014 at 04:00 PM EDT
The latest craze sweeping San Francisco: Follow Twitter clues and find cash stashed around the city.
Created last Thursday, the Hidden Cash
account already has over 150,000 followers – all in search of $100-filled envelopes that an anonymous donor has hidden in such spots as Dolores Park and City Hall. So far about 50 envelopes totaling $5000 have been claimed.
It's a simple concept with a rewarding payoff.
A hint is Tweeted as to where to find the money. When someone tracks it down, they Tweet their find – and a picture of themselves with the cash.
The playful donor behind the game wants to remain anonymous, but tells PEOPLE he is a wealthy real estate developer between 35 and 45 years old who builds homes and sells them for a large profit. Why share? He explains that he wanted to give back to the community in a fun way.
"There is nothing wrong with donating money to a traditional charity, but I also wanted to donate in a more spontaneous way," he says.
He adds that he's willing to keep the game going into the hundreds of thousands of dollars.
"This is intended to put a smile on people's faces," he says. "I can show people that they can pay it forward."
The most rewarding part for him so far is reading that people are doing just that. "They're posting that they're sharing the money they find. They're buying lunch for their office
or sharing most of it with fellow beachgoers
," he says.
One woman posted on Twitter, "I wish all millionaires followed @HiddenCash's lead. This IS the very meaning of paying it forward."
Next stop for the game: Los Angeles.
"I want this to expand to other cities," the donor tells PEOPLE. "I want this to become a movement."