What are some techniques for handling an abusive boss?

Of course this varies on a boss-to-boss basis, but one technique I had success with was responding to ridiculous demands with a silent stare that also says “I am having a violent fantasy in my brain about you right now” and my boss really started softening up after that. The thing is you don't even have to have the violent fantasy, you just have to convince your boss that you might want to murder them. This works especially well if you are large or menacing.