While it was on, Lost was my favorite. I think Flashfoward had potential, as did The Event. Not sure if Haven will be coming back but it doesn't seem like it. As for others, from favorite to least:
The Mentalist
Person of interest
Once upon a time
House
Alcatraz
Grimm
Most seem to flip around, though. The only one that has been consistently good to me has been the Mentalist, whereas others seem to have either really good or really bad episodes. Grimm always seems cheesy, and Once upon a time does, too, but to a lesser extent and has much more enjoyable characters. House has gotten to be the same old every single episode, so I'm glad it's ending. Alcatraz has that problem, too, but not in the same way and some of the characters are still interesting to learn about. Person of interest took a bit of time to grow on me, but it has, and maybe I'm just a little biased because the latest episode reminded me particularly of Lost.
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About suffering they were never wrong,
The Old Masters: how well they understood
Its human position; how it takes place
While someone else is eating or opening a window or
just walking dully along...