I recently learned on ‘Stuck in Customs’ (Trey Ratcliff), that you can tone map a single image in Photomatix.  I’ve tried this on several images, and like the result.  It really came in handy for some shots I took in Grand Teton where I forgot my tripod.  But I did notice that in pictures with a large Dynamic Range the single image version is a little more blocked up then a 3 image file.  Makes sense.  I guess nothing is free.  See if you can tell which is the single image.