Super rich generous guy hides envelopes of cash all over the city. You find it, you keep it.

In the scavenger hunt to beat all scavenger hunts, a millionaire in San Francisco has been hiding envelopes filled with cash around the city and then tweeting clues as to where they are hidden:

The unnamed do-gooder has been using the Twitter handle @HiddenCash and has given away nearly $4,000 so far – with each cash envelope holding a random amount of money up to $100 a pop.

Choosing to stay completely anonymous, the only clues we have about the mystery money spender is that he/she are a real estate magnate and is between the ages of 35-45. Sadly for us, there are plans to expand the hunt to New York and Los Angeles, but not Australia. Yet.

The millionaire wizard behind the game has said they hope it will encourage more random acts of kindness in the future.

And people in San Francisco have been loving it, thanking @HiddenCash with tweets and pics of their cash stashes.

Here’s hoping someone in Australia has the same idea soon. How about it Gina?