Recently, I have watched THE WORST series finale I have ever seen: the finale of How I Met Your Mother. Sorry if I'm offending anyone.

Then I thought, what was the BEST finale of a series? Boy Meets World was the first to come to mind.

Cory: "You coming with us, Mr. Feeny? You gonna sneak up on us in Central Park or something?"
Feeny: "No, I shall remain here."
Cory: "No, you'll always be with us. As long as we live, okay?"