In NYC, a storefront for Forever 21's Cirque 21 line, touting the circus-themed collection as "The Greatest Show on Earth"--sorry about the difficulty reading the image; I am not a photographer.
In Virginia, a pet store's "Woof Trap" display (Wolf Trap is a local concert venue) with various pet-themed bands.
The Kidillac, a toy from about 1953, according to the Smithsonian Museum of American History, a gift of Elmer's Auto & Toy Museum.
If you represented the respective trademark owners, which if any of these would impel you to write a letter? How good would your dilution claims be?