Here's an interesting marketing dilemma.
From Garage Spin.com Why "bar code" album artwork is bad
I saw this and chuckled. You didn't even need a bar code comparison application for this.
An 80's Hits compilation album was released in the UK with an enormous bar code displayed on its front cover.
That alone wouldn't be a problem; however, cashiers are apparently scanning the huge bar code, instead of the real one on the back of the album.
That wouldn't have been much of a problem either, except the bar code actually works, identifying a Jack Johnson CD being sold at 40% off.
Graphic designers beware!