Pushing Daisies. Writer's strike killed the show. When I saw Lee Parce on Twilight (WITH RIFFTRAX OF COURSE) I had to rewatch a few episodes.
Here is our winner.
Also, Dead Like Me. They tried to wrap it up with a direct-to-DVD movie and it was awful. It needed so much more time in the oven.
Stargate Universe needed another season as well, it was just getting to be amazing.
Sarah Connor Chronicles had me out of my chair yelling at the TV when it ended, but I'm ok with it now. Similar ending to Stargate Universe, honestly. Finishing on a world of possibilities ending seems oddly appropriate for both series. If they had to go out, that's probably the best way to do it.