What are your favourite sci-fi series finales, and which ones were disappointing, just plain bad, or made you mad?

My fave is The Prisoner's Once Upon a Time/ Fall Out (the two final episodes but they really went together). Fall Out actually received severe fall out from many people who felt it was too ambiguous, didn't tie up the loose ends properly (offered more new questions than answers), or was too darned wack! I loved it, that it made others angry at the time makes me love it even more! :D

Another great one must be Galactica 1980's. I don't remember the final episode, but the fact that it ended is worthy of some kind of thankful recognition. ;)

Didn't like the Voyager finale, nor how Earth: Final Conflict ended (I actually felt that show jumped the shark long before it ended).
Of course the worst finale is those that have none at all -- are cancelled before they even make the final episodes and are just left in limbo...

So what are your choices? (might avoid divulging spoilers or warn people of them)
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