I don't get it

There is a phrase and variations of a phrase that I have been seeing all over the place, especially in the knit blog world. Would someone be so kind as to enlighten me as to the meaning of "I can haz...?" There is always an overuse of the letter z and the grammar is appalling. Am I just being too uptight? Does this bother anyone else? Is it someone's way of being funny? I just don't get it. Please explain.