This CDC and elk hair dry fly is rapidly becoming my favorite go-to fly for mountain trout. I found it on a blog not long ago, tied up some and went out to the French Broad River and slayed 'em two Sundays in a row. The fly was fashioned by Hans Weilenmann of the Netherlands. You can find the instructions and more flies by Hans at www.danica.com/
The really neat thing about the fly is that you use only two bits of material, one CDC feather and a small clump of elk or deer hair and there are only two steps to tie it.
And, here's the kicker, you can fish it part of the float as a dry and then give it a little jerk to pull it under the water and fish it as a wet fly emerger.