Bringing Drama into a Cloudy Day
The soft and flattering light on cloudy days can be some of the best for photographing people, as the light doesn't throw harsh shadows. On the other hand, overcast conditions often produce dull, low-contrast pictures because there isn't enough difference between the shadows and highlights.
Film photographers switching to a warm and saturated slide film can help cheer things up, as this adds contrast and color. Digital photographers can easily do this process in the virtual darkroom. Alternatively, you can put your subjects under a tree or some overhang that will force the light to become more directional. You'll need a fast film for this, and there still might not be enough contrast to make the picture interesting. When shooting with a digital camera, image processing software comes to the rescue with its ability to increase contrast and color saturation.
If you have to take pictures on a dull day, you'll generate more interest by capturing strong lines and diagonals to keep the viewer's interest. You can also take pictures that project a mood or a feeling that matches the directionless light. Large scenes can be made incredibly boring by dull lighting. Try moving closer and capturing the details instead.