My greatest strength would probably be my harsh, sometimes necessary, brutal honesty. It comes off as rude sometimes, but some people need a major wake up call.
My greatest weakness contradicts what I said above, but it's true. I am an avid liar/story teller. I am quite a boring person at first with new people and I tend to make up lies or stories in order to seem somewhat human/appealing. I have been trying to break this habit, but it's quite hard since lying is second nature to me sometimes.