Burma Shave signs were iconic American advertising from the fifties. Witty billboards posted along a stretch of highway so they read as a little snatch of doggerel, either advertising the benefits of shaving, or with a little safety message. Fiftiesweb has a collection of the old slogans, and more on their history.
Example:
If your peach
Keeps out
Of reach
Better practice
What we preach
Burma-Shave
and
On curves ahead
Remember, sonny
That rabbit’s foot
Didn’t save
The bunny
Burma-Shave