KINSHASA, Congo -- On this day, the first sunny day in a while, Omer Waka decided to stake it all on bamboo wall calendars, a calculated gamble in a city of hustles.

Lately, he had hawked soccer balls, brooms, watches and belts, sunglasses, clocks and rainbow feather dusters. But visiting the wholesale market one recent Friday, he had a feeling about the 2007 calendars, one airbrushed with Jesus, the other with the Taj Mahal.

He took his savings, all $8 of it, and bought 10, figuring that he would sell the bunch on the street for $16 and that today he would eat.

"We're pulling into December, and I thought people would like these," said Waka, 31, a trained mechanic who has tried and failed to find work as a mechanic, as a driver, as a guard, as anything in a city where regular paying jobs are almost nonexistent.

And so for 12 years, he has competed in the daily roulette known as the informal economy, an off-the-books netherworld of scrappy enterprise that somehow keeps this city functioning and which includes the vast majority of its 6 million people.

Across Africa, cities are growing rapidly, with 35 percent of the continent's population now living in urban areas, a figure the United Nations expects will surpass 50 percent by 2025.

In Congo, hundreds of thousands fleeing civil war have come to Kinshasa, with one result being a capital filling up with the formally unemployed, who are nonetheless working.

Here, scenes of lethargy are rare; instead, there is the alert energy of people whose daily survival depends on creating something out of nothing, from the jobless teacher selling ices on the corner, to so-called passers whom travelers pay to get through the chaotic airport, to a growing number of street hawkers such as Waka who roam the wide boulevards selling bananas, or knockoff Roberto Cavalli fashions imported from China.

"You can't just cross your hands," said a woman who got a loan from a friend to buy bee pollen pills that she sells from her home. "You'll die of hunger."

To a large extent, it has been this way for decades in Congo, a country with immense mineral wealth whose people are nonetheless ranked among the poorest in the world. The cultlike dictator Mobutu Sese Seko, who ruled the country for 32 years, pillaged billions from the government to fund his lifestyle and patronage networks, leaving a state near total collapse and a nation of people who essentially had to fend for themselves.

Two civil wars that followed only worsened the situation, and thus in Kinshasa, urbanization has meant heaping more people on top of an already untenable situation.

For a few, there is still the marbled, if slightly decaying Grand Hotel left over from the Mobutu days, where Congolese and European businessmen do deals under the palms. Down a decrepit road behind wrought-iron gates is the gilded compound of the former minister of mines, who receives visitors on overstuffed couches and, for ambience, plays the same Sade song all day, on repeat.