I have always been fascinated by phrases and colloquialisms and word origins. I think we use some out of habit and I know we sometimes use them without really understanding them.

I love the knowledge within this discussion forum. I look at it often as an academic resource that has significant history and human knowledge that could be studied. When I talk about the Mudcat to those who don't know about it, I mention that it does contain academic knowledge that may not be known or discussed otherwise. One category of this knowledge that I always mention is etymology, the study of word origin. I think it includes phrase origin as well.

I remember a court case about "Dust My Broom". These fatcat assholes who take over estates of dead bluesmen suing each other over who came up with this first.

Zora Neal Hursten wrote about a lot of Southern phrases in the 1930's I believe.

I bought a phrase dictionary once that had origins to a lot of phrases, thousands upon thousands. Most of those were the very old ones though, mostly that originated in Europe. I can't find that book now, but its great. I hope there is a book out there that includes a lot of the newer ones too.