Oh, it's the best. I spent most of this last month working and training at the circus and picked up a little more - nobody actually uses it SERIOUSLY any more (apart from basic equiptment/act terms and the like), though that's probably because a lot of it comes from Romani curse words (or just plain made up for convienience), and in the U.S. at least the circus community has become very diversified. Most likely you'll just get beat up for trying to use it (or, if lucky, a pie in the face..).
...Er, pardon. I tend to ramble about such things. O_o