If you have, say, a smart home and several smart devices lying around, perhaps you have read of the possible hacking of your home or devices. If you are concerned and would like additional security protection, here's an article reviewing three security devices: CUJO, Dojo and Keezel.
If you're really, really geeky, here is another article with a review of one of the devices: CUJO.
After reading both articles I've concluded I want none of the devices. I don't have a smart home, and I'll protect my computers and smart devices another way.