Go check out this awesome gallery of colored smoke photographs by Graham Jeffery from England. They are shot against a black background while being side or back lit and then manipulated using a Hue/Saturation adjustment in Photoshop (the white background versions are simply inverted and then adjusted).
via ektopia

I think I saw the virgin Mary in one of them...
Posted by: Homer | July 25, 2005 at 03:50 PM
It is awe inspiring!!!
I really would like to know how you did it. Wonderful!!!
Congratulations
Elenir
Posted by: Elenir Marins | August 10, 2005 at 04:57 PM
awesome
Posted by: adam | May 02, 2009 at 05:43 PM