Anyone who "borrows" it isn't human, they are sub-human.

Who do you want to prevent from taking it? How much time would they have and how much work would they be willing to go to? Even the best lock out there is just a deterrant. The better the security, the better the deterrant.

Something right in the middle of a busy office might be a little different than somewhere that is deserted half the day. You could always get one of those laptop lock, but you still need a way to lock the empeg into the box itself.