I used to run a TFTP server on my router that held the decryption keys. As soon as a machine got far enough in the boot sequence to get network access, it would pull the decryption keys from the router. That way a thief would have to steal the router along with the computer, and have the router running when booting up the computer. It works wirelessly, too!

The scary thing? Define “new”. This judgment is from a lawsuit in 2014. So any car made in at least the last 9 years is doing this. Maybe newer cars are doing even worse things.