Hypocrite

Wikipedia's Definition:

"Hypocrisy is the act of condemning another person for an act of which the critic is guilty"

Answer.com's Definition:

1. The practice of professing beliefs, feelings, or virtues that one does not hold or possess; falseness.
2. An act or instance of such falseness.

M.e.o.w.'s definition of Hypocrites...

"Hypocrites are 50% of the people around us, whether you notice it or not. They often come conveniently in a package which consists of self centered-ness, cockiness, and a good deal of acting skills. These obnoxious people often talk too much for their own good, thinks they're all that, expecting the world to revolve around them. More often than not, they are actually the ones with the most flaws, and yet, they think of themselves as perfection brought to life. In actual fact, they are the perfect example to "empty barrels make the most noise". Normal habits include breaking promises, difficulty in being punctual, and a most admirable talent in creating an impressive amount of excuses that almost sound believable. Somehow, they make themselves sound so righteous, and they deserve exceptions. The professional hypocrite is capable of creating an impression that they are not a hypocrite at all, and hence is able to perform the crime in broad daylight without getting caught.

How to deal with Hypocrites:

If you're feeling nice,
Smile and laugh it off. That way you don't have to lie. If you lie, and agree despite the truth, that makes you no better than the hypocrite him/herself.

If you're feeling sarcastic,
Casually remind them with an excellent example of the criminal in action, and tell them what a great joke it was, that you nearly thought that the person was really a "hypocrite".

If you have a crush on that person,
You will think that person has no flaws, and you'll probably not realize that he/she is being a hypocrite at all. Just stare and drool since he/she is talking to you. Agreeing under crush-influence is excusable to a certain extent.

If you really hate that person so much you get constipation just thinking about that person,
Record that piece of conversation, and play it out loud (or repeatedly) the next time the crime is committed by the hypocrite."