boy howdy
1.  Expression similar to "Oh, gosh".

2.  Expression meaning "Oh, gosh, I'm a hick".  If you can use "boy howdy" in a sentence with a straight face, you're about as far out of the urban mainstream as I can imagine.
1.  Boy howdy, those sure are a lot of apples.

2.  Boy howdy, I'm goin' to the big city.  Topeka, here I come!