Granted this method will not work for everyone, because we all have different hair types. My hair is not oily at all, its dry, this may not work for someone with oily hair.
My hair used to be frizzy with lots of static and when I wore it down I had to use a lot of moose or gel. Now all I use is conditioner, two different types in the shower and a leave-in conditioner after! I only wash my hair every other day and I usually rinse it in the shower if I'm not washing it. My hair is healthy, smooth and soft!
I don't have before and after pictures, but if you're familiar with the Harry Potter movies, think of the transformation Hermione Granger's hair had from the first movie to the last!!!
You can read my first post with more details and other methods I tried here: http://www.testingtrisha.com/2012/10/no-poo-for-me-no-more-shampoo.html
When I first started this method I lived in a very humid climate and now I live in a very dry climate, thankfully I have not seen any changes. Once in a while my scalp does get a little dry and I will use a dandruff combo shampoo/conditioner, I only use a little just on my scalp and then I wash with both my usual conditioners after.
I have changed the brands of conditioner I use since I first tried this. For "washing" in place of shampoo, I use Tresemme Conditioner, then I use Dove Quench Absolute Conditioner and after showering I use Garnier Fructis Leav-In Conditioner.
Still think I'm crazy? I didn't come up with this idea on my own, if you Google "shampoo free" you will find a lot of information which is exactly what I did to begin with!
Are you shampoo free or considering trying it?