Hmm...  Has a few strange bugs. :/  Might need a little more tweaking when used - or some explanation for other settings that affect it. (Could also be some other stuff in the shader combining with it, will have to do some more tests.)

Apparently two things affect it - light through transparancy, and reflections of reflective material.

Top one has light through transparancy checked on both the basic render and the indirect lighting settings. Bottom one has both light through transparancy settings unchecked, but the strange artifact still occurs where there's a reflection of a reflective material.

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Barbequed Pixels?

Your friendly neighborhood Wings3D nut.
Also feel free to browse my freebies at ShareCG.
There might be something worth downloading.