I made this tonight in Photoshop, but it seems unlikely that I'm the first to come up with it. Feel free to take it and spread it around, I disavow any claim to copyright.
The above version is one of Flickr's smaller sizes for the thumbnail. The full size version, 3000x1200 pixels, suitable for printing at 10 inches wide by 4 inches high, at 300 dpi, is here.