Most Offensive Thing to Say

-GregR (gregr at gregr dot org)
-Virgil (virgil at yak dot net)

I'm trying to think of the most offensive thing that one could possibly say. I'm not talking about "you pussy", "your mom sucks donkey balls" etc, but something that when said to you feels like a punch in the stomach, something genuinely offensive. Additional points for the larger number of people that would be offended.

What is it that makes certain things deeply offensive? Go ahead try your hand at getting to the essence of what makes something offensive. Experimentation is encouraged.

Notes:

In dealing with sexual things, recall that there are at least two genders, men and women -- preferably both would be offended by the same statement.

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