stormdog | (no subject)

So I had a discussion with someone about the act of trolling. My perception of the act comes down to this: it's ok to cause annoyance, discomfort, or otherwise have a negative effect on someone's day in order to amuse yourself. At heart, it's a statement that the troller's personal happiness is more important than the trollees' happiness.
Don't misunderstand; I see examples that I think are funny as hell too. I just don't believe that they are ethically defensible, regardless of relative severity.

What do you think? Are there occasions when it's something minor and just good fun? Where's the line?