How to send Ctrl-Alt-Delete to a headless virtual machine in VirtualBox

Of little interest to almost anyone, but of great interest to those who need it:

VBoxManage controlvm the-server-name-or-uuid keyboardputscancode 1d 38 53 9d b8 d8

It also works for GUI-based consoles when you want to send the command from the host OS.

I'm hoping Google picks this up so others can find it...