My first critical application of upside down packaging tape was to
keep my cat off of the windowsill in a cat-hostile apartment complex.
Now that I'm temporarily fostering three kittens... They start
chewing on a group of electrical cords in a very small area on the
floor. Put two pieces of 4 inch long packaging tape among the
electrical cords. Reapplied as necessary. I just love it when they
start whining about having the tape stuck to them, and I get to come
to their rescue It's like cat correction heaven. One half hour to
one hour later, no more chewing on the electrical cords. BOOM.

If you've ever seen what household current can do to tool-steel in an
instant (like when you accidentally cut through it), you will freak
out at the thought of your cats accidentally chewing through an
electrical cord. It just can't happen.