Had two open-ended endings. Both Episode 26 and End of Evangelion show two possible outcomes of the Human Instrumentality Project.
Has an EPIC, end-of-the-world-as-we-know-it ending. There is nowhere for the story to continue after the final episode.
The endings to 0079, 0080 and SEED were all satisfactory. The others, perhaps not so much.
This show was a comedy, there wasn't any on-going plot. The ending provided emotional closure for Haruhi and Tamaki.