A couple of months ago I came across this fun bit with the whole audience, where everyone holds up a hand, and eliminates one at a time until they are all "accidentally" flipping the bird. I'm fairly sure it was in a mentalism book but for the life of me I can't find it again. I didn't make a note of it at the time because I figured it was one of those things I'd never use, and now of course I have the perfect place for it. If anyone knows I'd be eternally grateful.

Woody Aragon "A book in English", I believe. Also the Woodyland dvds.

I looked at the contents list of the book, and I saw nothing similar to what the OP described. Are you sure? Anyone know the name of the effect?

I could be wrong. the effect is called "ring divination".

It's in woodys penguin lecture also

Perfect, thanks guys

Thanks a million everyone. Ring Divination was what I was looking for. When I went through the index I was looking for other words, so I missed it. Thanks so much. I leave in the morning for a week long trip with a large group and this will be perfect for a late night campfire!

Edit: I did see this on his lecture, I watched it a few months ago and I guess I thought I had read it in his book.