I suspect that at least the part of the furver over the ME3 endings has something to do with the notion that this generation of fans may not have had ample exposure to how big a letdown a series ender could be; so that what this thread is for: What are the worst endings you have experienced/remember (TV, Movies) and which, if any, mattered to you at the time?

Since I expect only a few would recall this one, I'll kick it off with an older example:

St. Elsewhere
the entire five year run had all been the imaginings of an autistic boy.

Does Crystal Skull count as the Indiana Jones 'ending'?

Captain Kirk's death scene in Generations might qualify.

I hear people didn't like the Sopranos ending.

I thought that ST:TNG was having the worst ending ever, but then the last few seconds turned it to awesome.

I thought the Battlestar Galactica ending was awful. "We fought so hard to keep our culture in the face of war, now that we've made peace let's destroy our spaceships and live in mud huts"

Who thought that was a good idea?

Dark Skies had a terrible ending too... "oh no we've been cancelled, let's narrate over the top that now it is decades later"

I am Legend - with will Smith. The last man on Earth is not alone. Nor is he the last man because there's a bunch of people in a frickin walled town at the end!

Neon Genesis Evangelion (an anime) - The ending went mind tripping crazy.. it was, in a word, dumb. I cannot even begin to describe this bullshit. I remember a lot of people applauding and a lot of Tang.

Big O's ending was dumb as hell. I didn't expect anything deep, but I did expect some answers.

NGE is the worst piece of media ever crafted by mortal hands. Period. At no point during that shitstorm of a show was it ever worth the effort it took to sit on my ass and watch it.

It's simply impossible to be let down by NGE because it would have to actually raise you up at some point. If anything, the Ending was the best part, beacause it meant it was over.