(v) To, in any internet situation, achieve or appear to achieve logging in twice; that is, logging on while you were already online or apparently online. This term is based on a bit from the flash comedy animation "Arfenhouse," in which the character "Good Kitty" repeatedly reenters the scene by crashing through the same window, in some cases canceling out the previous version of herself that had just done the same thing. It is assumed that when you "good-kitty," you are actually logging on from a parallel dimension and destroying the previous manifestation of yourself.
When Jon's MSN messenger announced his online status twice, all of his contacts knew that he had just good-kittied.
To Good-kitty is to repeatedly log in due to malfunction.