I usually don't care about apparel brands, but I have a soft spot for Zara. They consistently create nice stuff for very reasonable prices. They make clothes that make you look good, as opposed to having attractive models looking good in whatever.
Their way of doing business is very hackerish (in the best sense), beautifully optimized.
No external marketing, they just put their shops in premium locations, letting their wares "sell themselves".
Instead of paying expensive prima donna fashion designers, they employ an army of young talented people. They constantly monitor fashion trends and consumer demands in their stores, able to rapidly innovate designs and change their production.
Their retail stock is completely rotated every two weeks, which creates an extra incentive for customers to come back to check what's new, and it also encourages Woot-type impulse buying, as the stock is limited.
Using state-of-the-art logistics they manage to keep their operations costs down. Thanks to their efficient procedures they can create better products for cheaper prices than competition.
$5.99. (just to save the long debate)
Checkout http://en.wikipedia.org/wiki/Zara_%28clothing%29 They are a Spanish company that do not outsource their manufacturing. They are able to keep their costs down and deliver the most trendy clothes to their customers. AA on the other hand made clothes that look like 1970s gym clothes.