When taking macro photos, you need plenty of light on the subject, to allow a reasonably large DOF (depth of field), yet keeping a reasonably fast shutter speed, and a low ISO. As a result, ambient light is typically insufficient, requiring the use of a flash.

However, using a bare flash will result in harsh lighting with harsh shadows, so it's important to diffuse and reflect the light to create a more pleasing photo.

This post provides details of the very cheap homemade reflector that I use for macro photography. Note that I can't claim credit for the idea, but I first saw it here on flickr.

With Australians being forced to switch from incandescent globes to compact fluorescent lamps (CFL), it's important to be aware of the fact that CFLs contain mercury. Breaking a CFL will release this mercury, and there are some significant health and safety issues associated with cleaning up this mercury, as well as disposing of CFLs.

On February 2007, the Australian Federal Government announced that incandescent light bulbs would be banned in Australia by the year 2010. Apparently that makes Australia the first country in the world to announce such a ban (ref 1, ref 2).

The primary reason for this ban is to encourage the use of compact fluorescent lamps instead of incandescent globes, as CFLs use approximately 80% less electricity, thus reducing Australia's greenhouse gas emissions.
Apparently by 2015, the switch to CFLs will reduce our greenhouse gas emissions by up to four million tonnes per year.