Yes, I think I have heard of it. I believe you can get it (cant remember the name of the place) at the little wooden looking stand in FL. For example, if you were walking from Matterhorn towards Its a small world, it would be on your right hand side, just before the place where you get your name drawn in colors and characters. They sell slushies and such. I have never had the drink, so not quite sure what it consists of. But I do believe it is green (big surprise, huh?).
HTH!
Brandy