I've seen a lot of portrait editing techniques and how-to's in various magazines and websites all with varying degrees of difficulty, software required and success.
So far my favourite is probably the simplest if you are looking for a sharp, HDR esque photo. You can also paint a mask on it to blend it a little more for a 'Dragan' style portrait. The tutorial for this can be found below and requires lightroom and photoshop (ideally cs5 or 6). This particular tutorial video is by ThatNikonGuy and you can check his other stuff out here.
These are at the extremes of the scale just to show what can be pulled out of an image. Note it will still cause some haloing but this can be either reduced with masking (or just tone down the luminosity layer, not every photo needs to look like this!).
Below I tried it with some posers from Fota Wildlife Park. The original images can probably be found in previous posts. I just wanted to see how non studio based shots would work with it.
Again these are both at extremes but they do work. They will start to show up messy backgrounds if you have them though (like in these shots). If I were to use this technique more I'd probably just highlight small parts of the subject with the technique as the full image definitely doesn't need it unless filling the frame or you have a black background.