Here are some of the shows that ended abruptly, leaving viewers wanting more.
Carnivale - HBO's surreal but critically acclaimed series ended with unanswered questions, piling up on all the other questions the show raised.
FlashForward - Since it was based on a book, you would think they could have ended it like the book did, but now, they ended it on a major cliffhanger that will never be concluded.
The 4400 - My wife and I really enjoyed this science fiction show. Now we'll never know what happens next.
Heroes - The series started out so great and ended so weakly.
Lois and Clark: The New Adventures of Superman - A super baby? Really?
Lost - While many people were debating the merits or flaws of the answers they provided, I was more frustrated by the answers they didn't give.
Mork and Mindy - Did the characters played by Robin Williams and Pam Dawber make it back to their own time and live happily ever after?
The Prisoner - Six escaped but will it all repeat itself?
Sliders - Did Rembrandt survive?
The Sopranos - Worst ending of all time.
Terminator: The Sarah Connor Chronicles - John jumps to a future that doesn't know him. And we'll never know how it turns out.
Twin Peaks - Agent Cooper is possessed by Killer Bob. Spooky, effective, but, darn it, I wanted more.
V - The Starchild is heading off to the alien visitors' planet on a booby-trapped spaceship and...we'll neverk now.
There are plenty more. Which ones did I leave out?