Worst one I've sat through in a while was when they aired Lady in the Water on TV a few weeks ago. I already knew everyone hated it, but I was willing to give it a fair hearing since I enjoyed both Signs and The Village. Urgh, it was dreadful. I didn't even make it to the end. Tedious, self-indulgent twaddle.
Oh, and I recently saw The X-Files: I Want to Believe as well. What a disappointment that was.