This stuff is my absolute favorite. It's $13, but, it works really well and it's not a pain when it comes time to wash it out. I notice that a couple I have used need a little more scrubbing in the shower. This is not one of them! Gives me awesome volume for my flat hair on my no wash days. Good Luck in your search!
I LOVE this dry shampoo. It's a great way to volumize your hair. http://www.amazon.com/Sexy-Hair-Volumizing-Shampoo-Ounce/dp/B001U6FIVE
However, it totally enables being dirty. :)