“Scrod” is a fish and not the passive pluperfect subjunctive of the word “screwed,” but there are jokes. A version of an old poem was printed in Time magazine in 1962:
   
“Here’s to old Boston,
Home of the bean and the cod.
Where the Kennedys always get caviar
And the McCormacks only get scrod.”
   
The standard joke involves a visitor to Boston who asks his taxi driver, “Where can I get scrod?” The surprisingly educated taxi drive says, ““I’ve heard that question a thousand times, but this is the first time in the pluperfect subjunctive!” The joke has been cited in print since at least 1969. T-shirts stating “I got scrod on Martha’s Vineyard” have been sold since at least 1977.
   
   
Wikipedia: Scrod
Scrod or schrod (/ˈskrɒd/) is any of various whitefish, such as young cod or haddock, that are prepared and eaten as food; often the preparation involves the whitefish being split and boned before cooking. Historically, scrod was a feature on menus associated with elegant New England dining; young cod are the mainstay on modern menus presenting the fish, and it is a staple in many coastal New England and Atlantic Canadian seafood and fish markets, and at many restaurants. The term “scrod” may derive from the Dutch schrod, implying cutting or shredding, or from Cornish scrawed, where it connotes splitting and drying of the fish (though a variety of apocryphal acronyms and origins have been suggested for the term). A method of preparation of scrod that appears historically, as early as the 19th century, is scrawing, which involves a drying step before the fish are broiled or otherwise cooked.
       
Google Books
Time
Volume 80
1962
Pg. 72
Here’s to old Boston,
Home of the bean and the cod.
Where the Kennedys always get caviar
And the McCormacks only get scrod.
 
Google Books
The New Frontier Joke Book
By Gene Wortsman
Illustrated by Robert Maxwell Weber
New York, NY: Macfadden Books
1963
Pg. 20:
We hear that Berlitz is putting in a new language course primarily for Americans. It’s called Boston English.
 
Here’s to dear old Boston, Home of the bean and the cod, Where the Kennedys always get caviar And the McCormacks only get scrod.
   
12 June 1969, The Daily Standard (Sikeston, MO), pg. 2, cols. 5-6:
A Chicago salesman on a business trip to Boston had a few hours to kill before catching a plane home. Remembering an old Friend’s advice to try some broiled scrod, a favorite fish in Boston, he hopped into a cab and asked the driver: “Say, do you know where I could get scrod around here?”
 
“Pal,” replied the cabby, “I’ve heard that question a thousand times, but this is the first time in the pluperfect subjunctive.”
     
6 January 1972, San Francisco (C) Chronicle, Herb Caen column, second sec., pg. 25, col. 1:
You no longer have to go to Boston to get scrod, you should excuse the past participle (and old joke).
 
1 October 1973, The Signal (Santa Clarita, CA), “So I Hear” by Mimi, pg. 2, col. 1:
JACKIE VERNON gave a speech to the editors of UPI this weekend. He told about a friend who was a great seafood fancier, and wanted to try that old New England specialty: scrod. Got off the plane in Boston, and said to taxi driver: “Where can I get scrod?” Taxi driver: “I’ve been asked that question a thousand times, but never in the pluperfect!”
 
29 July 1974, San Francisco (CA) Examiner, “Salty tale from Boston” by Dick Nolan, pg. 27, col. 1:
The most ancient of “scrod” jokes has to do with Boston, of course. A visitor there asked this taxi driver, “Where can I get scrod in Boston?” And the taxi driver is said to have replied approvingly, “How refreshing to hear the pluperfect subjunctive!”
 
7 May 1976, The Irish Times (Dublin Ireland), “The First Thirteen” by Owen Dudley Edwards, pg. 13, col. 3:
Characteristic anecdote—lady (in quest of sea-food): Can you tell me where I can get scrod? Policeman: Man and boy, I’ve been asked that question 1,000 times but this is the first time I’ve been asked it in the passive pluperfect subjunctive.
   
25 September 1977, The Sun (Baltimore, MD), “Sundires,” magazine sec., pg. 2, col. 5:
The T-shirt had a drawing of a seafood restaurant and the words, “I got scrod on Martha’s Vineyard.”
 
Google Books
Sweet Anarchy
By Nathaniel Benchley
Garden City, NY: Doubleday
1979
Pg. 305:
Dark glasses and cameras were the rule, and some individualists sported T-shirts with comical mottoes like “I Got Scrod Last Night—What Did You Have?”
   
Google Books
Dirty Stories for All Occasions
By Andrew L. Cleveland
New York, NY: Galahad Books
1980
Pg. 15:
He leaned toward the cabbie and said, “Tell me, mister, do you know where I can get scrod at this time of night?” The cabbie scratched his head for a moment and answered, “You know, sir, in my 20 years in the taxi business, I’ve been asked that question over a thousand times; but I must tell you that this is the first time in all my experience that anybody has phrased that query in the past pluperfect.”
 
Google Books
Words on Words:
A Dictionary for Writers and Others Who Care about Words
By John B. Bremner
New York, NY: Columbia University Press
1980
Pg. 71:
A fish-starved Nebraskan arrived in Boston and asked a cab driver “Where can I get scrod around here?” Replied the cabby: “How delightful to hear the pluperfect subjunctive!”
     
Google Books
What’s the Good Word?
By William Safire
New York, NY: Avon
1983, ©1982
Pg. 32:
Boston tourist: Excuse me, Officer, can you tell me where to get scrod?
Policeman: I’ve heard that question asked a hundred times before, but never in the pluperfect subjunctive.
 
Google Books
A Few Words
By Laurence F McNamee and Kent Biffle
Dallas, TX: Taylor Pub. Company
1988
Pg. 68:
Visitor from Boston: “I say there, where can I get scrod around here?”
Policeman: “Where are you from, Jack? I’ve heard the word a hundred times, but this is the first time in the pluperfect subjunctive. ”
 
Salon
MONDAY, JUL 1, 2013 07:15 PM EDT
The 10 nerdiest jokes of all time
Courtesy of a Reddit thread, these will make you the toast of your next philosophy study group
THERESA FISHER
(...)
5. Tense mood? Break the ice:
 
“A man is on his first visit to Boston, and he wants to try some of that delicious New England seafood that he’d long heard about. So he gets into a cab, and asks the driver, ‘Can you take me to where I can get scrod?’ The driver replies, ‘I’ve heard that question a thousand time, but never in the pluperfect subjunctive.’”
(...)
COMMENTS
Bob B Jul 2, 2013
For the record, the scrod joke appeared in Playboy magazine back in the sixties.