I thought this was going to an alternative to a physical lock, which seemed impossible, but on my way to click on the link it occurred to me you could setup the

I thought this was going to an alternative to a physical lock, which seemed impossible, but on my way to click on the link it occurred to me you could setup the Mac so it sounded an alarm if moved, unless you unlocked it with your password. Which would be also be a cool idea. (Since I am at a cafe I guess my mind went more towards physical security.)