I'm going on vacation and I want to turn off Zen Cart while I'm on vacation ??

I've used V-bulletin and they have a turn off button in the Admin section. Does Zen Cart have the same thing ??? If not what other options are there ??

I have looked in the Admin section for a turn off switch but I can't seem to find it. lol

P.S. thank you for making a great program ... this is the best program for business that I have ever seen ...