You do realize that Josh isn't actually intending to give Potato away or suck a dick, right?
It's basically a statement that he feels something is so far from reality that he would do something beyond consideration.
Also - and this may come as a shock - when someone says "I'd give my left arm to....." - they are also not seriously offering a major limb.
-Ever notice my tagline? "Be honest..." If you say something, mean what you say and speak only the truth as you know it. I get your reference to "I'd give my left arm to...." or as I've heard it said, "...left nut..." Talk can be cheap. It doesn't have to be though.
Some people say it's just the internet and what's said doesn't really mean anything. Well if that's true, then it is even a bigger waste of time than we already know it is.
Yeah, I can be all serious sometimes. Someone needs to be. It keeps things in perspective.