For the shot I posted yesterday, I really wanted to get a low angle, with my camera just above the surface of the water. Unfortunately, I was still wearing my pajama pants and I didn't want to kneel or lie down in the green scum that ringed the water line. On the other hand, the scum made an interesting subject in its own right.
Technical info: Shot with a Nikon D40 and Nikkor 18-55mm DX lens, in manual exposure mode. Focal length 55mm, aperture f/5.6, shutter 1/30 sec, ISO 200. Post-processing in Aperture 3: Daylight WB preset, crop to 4x5, s-curve to increase contrast and set the white and black points.
Thoughts for improvement: I like the horizontal bands of color and focus in this shot. I'm not 100% sure about the crop--it might look a little better with some more space at the top. I would also have liked to see what it looked like with a narrower aperture (more depth of field) and the focal point set either right at the water line or further into the foreground.