The Weiss Distribution Technique (WDT) has become widely used as one of the best methods for declumping, fluffing and distributing grounds. The benefits of this cannot be overstated as they prevent channeling and provide even ditribution for the best extraction and consistency. This WDT tool has stainless steel "legs" and a walnut handle.
 
Here is an article breaking down the technique by John Weiss the one credited for creating or at least popularizing it:
 
Improve your Espresso with Weiss Distribution Technique