When I am using my computer, my cat often walks across the keyboard. Sometimes she renames files, selects and deletes text—once, she replied to an email. This became such a problem that I had to unplug my keyboard whenever I left my home.

But then, I developed CatNip—a program which, while running, detects “cat-like typing” and locks the keyboard, usually in under a half second. Optionally, CatNip will fade your desktop and display a warning message to your cat (which is of dubious value, since if your cat can read, your cat can probably type, too).