Deep in China's spirit world, an inflation crisis is brewing that would give central bankers chills.

For hundreds of years, Chinese have burned stacks of so-called "ghost money" for their ancestors to help ensure their comfort in the afterlife. The fake bills resemble a gaudier version of Monopoly money, emblazoned with the beatific-looking image of the Emperor of the Underworld.

Traditionally, paper money burned in China came in small denominations of fives or tens. But more recent generations of money printers have grown less restrained. The value of the biggest bills has risen in the past few decades from the millions and, more recently, the billions. The reason: Even Hong Kong's dead try to keep up with the Joneses, and their living relatives believe that they need more and more fake bucks to pay for high-cost indulgences like condos and iPads.

This year, on the narrow Hong Kong streets that are filled with shops that specialize in offerings for the dead, there appeared a foot-long, rainbow-colored $1 trillion bill. "What we have right now is hyperinflation," says University of Hong Kong economist Timothy Hau. "It's like operating in Zimbabwe."

The inflation problem is expected to worsen during this year's Hungry Ghost festival, when the gates of the underworld are believed to open and ghosts are allowed to wander the earth. For the next few weeks, residents across the city are staging traditional opera performances to entertain their supernatural guests (leaving the front row of seats empty for ghost spectators), cooking elaborate meals of roast meats for their enjoyment and burning wads of fake money on the sidewalks in their honor.