It is customary to ask for and receive "lekach" (sweet cake -- signifying a sweet year) from someone (usually one's mentor or parent) on the day before Yom Kippur.
One of the reasons given for this custom is that if it had been decreed, G-d forbid, that during the year we should need to resort to a handout from others, the decree should be satisfied with this asking for food.
The Lubavitcher Rebbe adds a deeper insight: "asking for lekach" on the eve of Yom Kippur instills in us the recognition that all the sustenance we receive throughout the year, including that which we supposedly "earn" by our own powers and endeavors, is in truth a gift from Above, granted in response to our daily requests from "He who nourishes the entire world with in His goodness, with grace, with benevolence and with compassion."
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Video: The Rebbe Distributing Lekach Before Yom Kippur
The Rebbe would also distribute lekach on Hoshannah Rabbah, to those who had not received before Yom Kippur. Click here to watch a video clip of the Rebbe distributing lekach on Hoshannah Rabbah of 5742 (1981); and here for Hoshannah Rabbah 5749 (1988).