Using smoke in a photoshoot is cool, it really adds some extra “oempf” to a shot, and it helps to mask uninteresting backgrounds of course.
When you start adding color to the smoke shot I always feel the shots are extra special.

 

In these shots I used a standard (cheap) smoke machine and one strobe with a red gel, as you can see I shoot under an almost straight angle into the light source. Because of the way smoke behaves you get a beautiful effect, adding a bit of Intensify pro from MacPhun (you can also use Topaz clarity of course or NIK tonal contrast) really finishes the shot.