Inherent in its name, Pow! is a powerful word, and even stronger as a visual. Many use it, but few take full advantage of it.
Case in point is The Gap. The web visual below mirrors what's currently being shown in their stores and storefronts.
But that's where the Pow! begins and ends. The offer (Buy One, Get One 50% Off) is an industry standard, and about as Surprising as mustard on a hot dog.
Perhaps we're somewhat biased here at Surprise Central, but if you're gonna use it, blow it out of the water. Don't cry wolf with the omnipotence of Pow!
(And while on the subject of the power of you-know-what, check out Barry Welford's musings on the marriage of the exclamation point to the word itself. Me and Stan Lee...I'll take it!)