At sundown today begins Yom Kippur:
Yom Kippur (Hebrew: יוֹם כִּפּוּר, … or יום הכיפורים), also known as Day of Atonement, is the holiest day of the year for the Jewish people. Its central themes are atonement and repentance. Jewish people traditionally observe this holy day with a 25-hour period of fasting and intensive prayer, often spending most of the day in synagogue services. Yom Kippur completes the annual period known in Judaism as the High Holy Days or Yamim Nora’im (“Days of Awe”). (link)
Despite the deep seriousness (and foodlessness) of the day, many have been tempted to play on the name, as here:
(Hat tip to Bert Vaux, who credited Russell Mystiek.)
As for kippers:
A kipper is a whole herring, a small, oily fish, that has been split from tail to head, gutted, salted or pickled, and cold smoked. (link)
Suitable for breaking the fast, though lox or smoked whitefish (and eggs, bread, and cheese) would be more traditional.