Interesting how some of the all time greats played upside down guitars as did Hendix .
That's because they were either pissed - or left handed.
As regards the plastic tube device used for oral modulation it was called a "talk box". Wikipedia can explain it better than me,
"A
talk box (also spelled
talkbox and
talk-box) is an
effects unit that allows musicians to modify the sound of a
musical instrument by shaping the frequency content of the sound and to apply speech sounds (in the same way as singing) onto the sounds of the instrument. Typically, a talk box directs sound from the instrument into the musician's mouth by means of a plastic tube adjacent to a vocal microphone. The musician controls the modification of the instrument's sound by changing the shape of the mouth, "vocalizing" the instrument's output into a microphone."
Peter Frampton was a key user. And never forget this classic example from Bon and the Jovi's,
Not to be confused with the electronic Vocoder used, famously, on Herbie Hancock's "Rockit" and other songs of the 1980s. More recently, Autotune has taken over the territory. I'm sure this forum is packed with Ke$ha fans!