Strike Gold Day!
You're extremely wealthy and you've just bought some homes from some poor people for far less than they were worth. The poor people took the offer because they didn't know any better and they were unaware that the sum you offered would not buy them a rotted out shack by the highway in today's market. But you wanted to open up a Harmful Chemicals Plant on the plot of land where their houses were, so you swindled them into near-homelessness.
Today you're going to level their homes and discover that the dirt is chock full of gold. All of those poor people could have been millionaires had they just dug a few feet under their basements and saw the glitter. Instead, they're all renting small apartments.
Now that you own the land, the gold is yours. While it is worth hundreds of millions all told, you really won't notice the addition to your assets and it will actually cause some problems for you come tax time.
Happy Strike Gold Day!