A simile/idiom similar in meaning to "one man's
trash is another man's treasure" only, in this
case, it means that what is funny to one person
may be offensive to someone else.
Tom: "Man, I told this hilarious
joke last night. Everyone laughed but Bob. He was a douche and said the
joke was offensive."
Dick: "Don't worry about it, dude. One man's LOL is another man's WTF?"