My favorite NPC would have to be 5. 5 was a goblin we captured in a 3.5 Eberron game. In typical PCs fashion, we interrogated him, asking him about his home and how many other goblins there were. However, it soon become apparent that 5 could only count to 5. 5 was the number of golblins in the heavily infested goblin ruin. 5 was the number of goblins that were currently terrorizing the valley. 5 was the number of miles it was away. We took the little goblin under our wing, and he traveled with us for several months, until we had to let him go, hopefully to become a farmer in the goblin nation, growing 5 things at a time.