When you reach the Fade in Dragon Age 2, you'll happen upon a pair of collections of barrells, each of which is a puzzle you can solve for attribute points. This video will show you the solution for each, earning you 3 shiny new attribute points for their completion and making your hero that much more badass.
From the Creator:
The first puzzle you want to get the little barrels on top of the big barrels.
The second puzzle you want to stack the red barrels on top of each other.