I'm not used to this small talk stuff... and just answering "ça va" feels quite unhonest.
@jlliagre: Good question... I'm German. 1) My impression is that people in Germany don't ask this question so often and so 'aggressive' like in France. Which never let me think about how i would answer this question in german 2) I can do different things: I can just answer "bad" or "I'm in bad mood" or answer with a ironic "fantastic". I can describe what i did recently or what i think, the way I make this description reflects my mood. I can distract from the question, to signalize that i'm in bad mood and don't want to talk about it. I also can use pictures to answer the question. Of course, it depends on the context and the relation you have with person. 3) Even if the most frequently answer on the question is something like: "gut, und selbst" (good, and you) its not disturbing for the other person when you act differently. Which is the point... I have the impression this is with the frensh style of communication not easy: Frensh is much more formalized than german, they work more with expressions and pictures.