This thread seems settled but I'd like to contradict almost the entire thing: Except in the cases of "Well done" and "Yeah, right", I would say that all of them have some sense of irony or sarcasm to them. "Well done" and "Yeah, right" depend on tone of voice and context.
One major point of contention: not all of them are inherently hostile. Things can be sarcastic or ironic without actually being hostile.
<ul><li>Nice try is the perfect example. There is a way of saying things in English that communicates sincerity. Nice try can be said sarcastically, as in "Yeah you tried and it was terrible" or as in "You tried, and it didn't work, but at least you gave it your effort." The first one is semi-hostile (even to a friend one can be hostile) and the second is sincere. In both cases nice try does not indicate the attempt was successful.</li><li>Surprise, surprise is almost never said in the context of an actual surprise. But it doesn't have to be hostile. It always seems to have irony.</li><li>Fine does seem inherently hostile to me. "That's fine." is how I would say something is fine without hostility.</li><li>If you are pronouncing "ha ha" as two distinct syllables and not genuinely laughing, it is sarcastic. In text this does not apply.</li><li>"Good luck with that" is absolutely sarcastic. I have never heard someone say "Good luck with that" and mean anything other than "what you are trying to do is impossible."</li></ul>
As for "Thanks a lot" I agree that it could be non-sarcastic and non-hostile, but I deliberately avoid using it because of how common the sarcastic use is. If I am trying to be authentic I say "Thanks". If I am trying to be effusive, I say "Thank you very much". "Thank you a lot" sounds fine to me, especially with a pause: "Thank you, a lot". It's also quite common to add "I mean it" to the end of any thanking phrase, especially if one says "Thanks a lot. I mean it." which subverts the common sarcasm.