De-anonymisation for one.

But more generally, if I’m the sort of person who would allow this I’d probably allow some other stupid permissions if they promised me something novel on the other side.

Maybe try hiding your face below the camera and throwing your hands up in the sky so the camera only sees your hands then play/sing Metallica.

   [Chorus]
   Never cared for what they do
   Never cared for what they know
   But I know

   [Refrain]
   So close, no matter how far
   It couldn't be much more from the heart
   Forever trusting who we are
   And nothing else matters