Sometimes the simplest solutions are best

If your time machines (which have and probably will again in this issue wrecked havoc with the time line) are stolen so often that you’re developing a tracer in order to hunt them down then you probably want to install some device that keeps them from being stolen in the first place. Here are my suggestions 1. Don’t leave the door unlocked and 2. Require an ignition key.

from Superman/Batman #75 (preview)