For something truly bizarre, take my HRE campaign. I had managed to excommunicate everyone around me (Eat that you French ). I received the 1000 florins almost every 3rd turn for about 15 turns (at which point the Pope went to God, then was probably denied heaven for being a hypocrite for attacking the Italians). It seems the Piety of your ruler, the number of nonexcommunicated catholic factions, and a random number generator (plus the popes "hidden" bank account) have something to do on whether or not you receive the gift.