Teller's advice on bloody heads

This is a useful tip from Teller's Macbeth which I think I will take up for our production

Today we did a conference call about heads. In Shakespeare’s day, you’d go to work and see severed human heads on display on public structures to warn prospective crooks of the consequences of malfeasance.

Shakespeare introduces the dead Macbeth’s head right at the finale of the show. It was natural to Shakespeare. You wanna show a dead butcher? Bring out his head.

But in the modern theater, you don’t see a lot of heads. And for good reason. If the fake head (and, yes, I’m sorry; we’ll probably have to have to fake it, except maybe on the final performance) looks bad, you say, “How lame!” and it takes you out of the story. If it’s good, you say, “Wow, that’s a fine reproduction. I wonder how they cast it,” and you’re right out of the story. It’s a no-win situation.

So we’re looking for a way to get the horror without the distraction. At this point, we’re thinking of establishing the convention that severed heads are carried around in blood-soaked burlap bags. What’s nice about that is that this combines two awful images we’re seeing from the Middle East nowadays. We see terrorist prisoners with their heads in bags, and we see people being beheaded. Put ‘em together and you’ve got Macbeth.

Macbeth becomes a tyrant who rules by terror, so it makes sense he would display the heads (and maybe bodies) of uncooperative subjects.
http://www.pennandteller.com/03/coolstuff/tellerspeaks/telleressayheads.html