Can't beat a good nose pick.
This guy is the image if one of my nephews....
What we do:
scream along to Child in Time by Deep Purple: the oldies will know what this entails.
Ditto The Immigrant Song by Led Zep.
Mime Wife Strangulation. ( actually...... wishful thinking) she has to pretend to be dead afterwards. Nobody has yet intervened: just looked the other way. 'Don't get involved, dear' syndrome.
Talk to people that only you can see in the back seat. Imaginary children for example. Bemuses the car behind. Does not apply when in the MG. if in the MG you then have to open the boot and pretend to talk to someone that is in there. Offering a bottle of pop into the boot helps with this.
Steering wheel bubble wrap? Entry level lunacy.