In the UK we just give a nod, or shake a left leg off the peg if overtaking.
Nodded once at at pillion passenger of a HA group overtaking me to be met with a stony stare. Didn't frighten me, I was going to take the next off ramp anyway !
If you do it today you MIGHT regret it. If you CAN'T do it tomorrow you WILL regret it.
