This is my current favorite Kat sketch.
I like this for a variety of reasons. Firstly, I love the way Kat fills out that very accurately-rendered uniform. Secondly, I'm enough of a Trek geek to know that there is a Trek race, the Caitan, of which Kat could be a member. So, in an alternate universe, there really could be an Ensign Kat on the USS Enterprise.