This is something I've been wanting to try for ages, and last night I finally got to do it - Smoke Photos!
The setup was pretty simple, black background, a stand with incense burning, flash to camera left, reflector disk to camera right.
Camera settings were D300 + Sigma 24-70, 1/250, f/14, ISO-200, SB-900 with cardboard snoot, wireless, at full power (until it overheated then I swapped to the SB-800).
The results:
Confusion
Tornado
Twins
The Mask - Can anyone else see what looks like a masquerade mask?
Pelvis
The setup shot.