Ninja Turtle saying Hi

My friend sent me this in MSN. She drew this by using the mouse. Amazing. Actually, she drew a knife, her angry face and my face the other day. But, I'm too careless to close the MSN window without saving it! :(

Anyway, do you think the drawing is good? To me, it's very good indeed. I was not able to draw it well by using a pencil, don't mention about using mouse anymore.