I usually only respond to something if there's a point to what I'm going to say. If someone had said something in the hopes of getting a reaction from me, I usually ignore it - by replying all you are doing is giving them more ammunition. I've been told I'm very difficult to argue with, because I don't rise to bait most of the time.
One in a blue moon I will release my inner Alexis Carrington.
OK that makes me Sable now, we must visit the Furrier....