Ernest Hemingway published this “blank verse” in his high school literary magazine in 1916:

Get it? David Morice followed up with this “punctuation poem” in Word Ways in February 2012:

% , & —
+ . ? /
” :
% ;
+ $ [ \

It’s a limerick:

Percent comma ampersand dash
Plus period question mark slash
Quotation mark colon
Percent semicolon
Plus dollar sign bracket backslash

(Thanks, Volodymyr.)