Last year I created some presets for Lightroom that cheat the tone curve to create an interesting look for smoke images. I've even won a local competition using them (€50 prize, thank you very much!).
Smoke images are a little 'stale' to heavy internet users, because to a certain extent, it's all been done before. Recently though, it seems there's a renewed interest. After noticing an increase in the number of downloads recently I found a post on Flickr referring to them. It prompted me into posting a previously unseen shot to show off one of the presets.
For this image, I've also used the Split Toning panel to add a little colour to the shot.
Canon EOS 5D Mark II
1/125 second
F/5.6
ISO 100
105 mm