So, I assume you all know the story about the Indian king who loved chess, and the grains-of-rice bet. To refresh your memories, or if you haven't heard that story: there was this king in India, who loved chess. Well, chatarangua, to be technical, which is the ancestor-game to chess, but, for purposes of the story, we'll just say "chess." And he'd play it with any other chess enthusiast who came through, offering prizes to those people who beat him.
So, one day, a sage comes through, and challenges him to a game, and says, if he wins, he gets one grain of rice for the first square on the chessboard, two on the second, four on the third, and so on, doubling each time for all sixty-four squares. The king tries to get him to accept more than just that, but the sage says that the prize he's suggested is enough for him.
So, they play, and the sage wins, and the king has them bring out a chessboard, and places one grain on the first, two on the second, four on the third . . . and pretty soon, he's stacking bags of rice, and barrels of rice next to the board, and real soon, he realizes that there is no way he can pay his debt. As it turns out, he owes the guy an amount of rice that's most of the biomass of the planet . . .
So, that's the story as I'd heard it. But it turns out that the legend goes on.
At that point, the sage reveals himself as actually Krishna in disguise, and says that the king can pay his debt over time. So he built the Ambalappuzha Sri Krishna temple, which has served payasam (which I am more familiar with under its Northern Indian name of "kheer") to every pilgrim that comes through every day since then. I can't find any data on how much rice they go through, but if they serve one ton of rice a day, they should be paid off in about eleven million centuries.