Patrick Wensink

Jack Daniel's sent one of the friendliest cease-and-desist letters that you'll ever see to Patrick Wensink, the author of a novel called Broken Piano for President, whose cover certainly makes use of the iconography around Jack Daniel's famous whiskey.
But, rather than get all threatening, the letter is quite nice, reasonable and even (somewhat surprisingly) accommodating. It starts out by admitting that they're flattered, not upset.