Yes. Many times. I talked to sign guy at the FLAG thing. The real trick is getting them to talk back.
When I'm back, in 3 years, if there's still a war to fight, I'm gonna try "Speak boy, speak!" and see if that gets a reaction from them. I also permit you all to use that. But it's copyrighted, so you owe me $1 every time you use it. And you need to take a $500 class on how to properly use it. Hey, I think I'm on to something here....