Updated

In South Korea, a disparate and colorful collection of activists is taking on one of the world's most isolated nations.

Their weapon of choice: homemade hot air balloons that float over the North Korean border and carry in the outside world.

Some activists send up plastic leaflets that weigh less than a feather and flutter down from the clouds with calls for democracy, or blurry cartoons ridiculing Pyongyang's ruler. Some send flash drives loaded with soap operas, or mini-documentaries about the vast wealth of southern corporations.

Their South Korean critics see them as little more than attention-hungry cranks who spend much of their time exchanging insults. But the activists look across the border and see a country they believe they are already changing.