New York delis used to feature these signs. It meant that they were selling the ends of a salami for five cents.
It was a good rhyme and a good business.
New York City Folklore
edited by B. A. Botkin
New York: Random House
[From "The Jewish Delicatessen," by Ruth Glazer, in the book Commentary on the American Scene: Portraits of Jewish Life in America (1953). This was originally published as "From the American Scene" in the magazine Commentary, March 1946, volume 1, number 5.]
Pg. 370: "A Nickel a Shtickel"
Pg. 371: And invariably on the glass-topped counter is a plate with small chunks of salami. In the old days the plate always carried a sign, "A Nickel a Shtickel." (A most convenient - and profitable - way of disposing of the ends of the salami, too.) This immortal rhyme succumbed during the [Second World] war to the free verse of "Have a Nosh - 10c."
15 August 1952, Zanesville (OH) Signal, "Walter Winchell On Broadway" column, pg. 4, col. 4:
Harry's Delicatessen (on 47th off B'way) still features "nickel for a shtickel" - chunks of salamee.
2 April 1972, New York Times, pg. A13:
There was Rosen's Delicatessen in Queens Village, where you got a small hunk of salami for five cents - "a schtickel for a nickel," he called it.
7 July 1982, New York Times, pg. C1:
"MENTALLY, I'm always noshing," said Mayor Koch, explaining the conflict he has between loving to eat and wanting to keep his weight down. "What I mentally nosh on most used to be called 'a nickel a schtickel' - those small end pieces of salami that were sold on top of the counters in New York delis for 5 cents."
4 November 1984, New York Times, "True Confessions of a Deli Addict" by Nora Ephron, pg. 425:
Sometimes I would chew on a miniature salami called a "schtickel" (there was a sign at Linny's that read: "A nickel a schtickel is a rhyme, now a nickel a schtickel is a dime") and press my nose against the glass case as a counterman sliced the Nova on the diagonal and laid it on sheets of waxed paper.