When I was in Colorado for last year's GABF, I had the opportunity to get up to Boulder and visit all 16 breweries there at the time. One of the winners, from both a beer and art standpoint, was definitely Twisted Pine.
Twisted Pine has a basic label that looks like this:
Not particularly stunning, but the combination of the simple elements would lead it to jump off a shelf while remaining approachable. Many of the beers use a permutation on this.
They also branch out, such as with label art like this (Ignore the promo stuff on the right):