Jabberwocky
Frumious Bandersnatch
^no prob 
actually yes I can see them being of great benefit to some... your knowledge of "how to move" in general when beginning would greatly determine what/any benefit there'd be here tho (for instance, someone who was athletic to the point of knowing 'bounds/limits' in general sense, and, maybe, has lifted weights and is aware of posture of the back and things like that, will be very very okay to jump right in. If you're the type that injures yourself picking crap up w/ hunched back, yeah you prolly need remedial posture/form for anything whether running or yoga)

I think intro class(es) are important for beginners to learn proper form.
actually yes I can see them being of great benefit to some... your knowledge of "how to move" in general when beginning would greatly determine what/any benefit there'd be here tho (for instance, someone who was athletic to the point of knowing 'bounds/limits' in general sense, and, maybe, has lifted weights and is aware of posture of the back and things like that, will be very very okay to jump right in. If you're the type that injures yourself picking crap up w/ hunched back, yeah you prolly need remedial posture/form for anything whether running or yoga)