It's an old stock investing yarn -- buy stocks in companies that make things people actually use, even in downturns. Everybody buys toilet paper, for example. So durable goods companies are often more solid than, say, the company that makes trendy footwear or peddles hard-to-define credit vehicles.

Yesterday's incredible stock market plunge put this saying into stark relief, when every single stock in the S&P 500 dropped, except for one...the Campbell Soup Company.

That's right. All 499 stocks tanked except for the guys who make soup. Campbell's stock edged up 12 cents, to close Monday (the worst stock market drop in two decades), at $37.75.

Campbell's, a 136-year-old company that still carries the gold award label it won for quality at the 1900 World's Fair, is the largest manufacturer of soup in the world.

It might be a stretch to say this proves Americans are through with high-flying Gilded Age nonsense and want to embrace its more humble roots. But maybe not.

Because pretty much everybody could use a nice bowl of soup right about now. And maybe a few goldfish crackers. Campbell's owns Pepperidge Farms, too.