The need for feline repellents goes back as far as humans have kept domesticated cats. Whether it's your own kitty chomping on your indoor plants or a stray digging in your garden, keeping them from making messes where people don't want them has been a continuing battle.
For those who prefer natural remedies, there are traditional nostrums and some new wrinkles in the war, all claiming success in keeping kitty out of where she's not welcome.