Hidden Cash is the Twitter handle of an anonymous person who is leaving stashes of cash in public places in the San Francisco Bay Area. The person said they had made “millions of dollars” in the San Francisco real estate market and he/she is looking for a way to give back. The person says they intend to stash cash once or twice a week and have no plans to stop. His/her explanation?

"There is nothing commercial behind this. It is a social experiment. I’ve made millions of dollars the last few years, more than I ever imagined, and yet many friends of mine, and people who work for me, cannot afford to buy a modest home in the Bay Area. This has caused me quite a bit of reflection. I am determined to give away some of the money I make, and in addition to charity, to do it in fun, creative ways like this. "