I saw Sam using this whilst prepping her hair for a tutorial and as a lover of massive volumised hair I had to snatch it from her to use!
It looks like a make up brush but in the casing it contains a texturising powder that is distributed out onto the brush in one click of the end.
I have seen similar products such as Dust it by Otis that do the same thing but I love that you can apply precisely where you want it with the brush.
It is kind of like dry shampoo that it gives bulk to the hair and refreshes lank hair between washes, although it claims to be suitable on all hair colours I would use it sparingly on dark brown or black hair as it may start to look a little grey and dusty.
A great little accessory for your handbag or to travel although rather expensive.
Check out http://www.shuuemura.com/ internationally but also available from http://www.feelunique.com in the UK at £31.00