I am crap with hecklers. For a start, I never hear what they actually say, so I have to say "Sorry?". Then, if they repeat it, I can never think of anything to say at all. So I tend to smile weakly, and get on with what I was doing.
   I would like to commend something I've always admired in JOhn from Hull's writing. It is a riposte he often uses. If someone writes a particularly insulting post directed at him, or posts a particuarly well-argued and well-documented reply to one of his assertions, he replies, very simply:
   "oh"