How Long can you keep cosmetics?

HOW LONG IS THAT GOOD FOR?

Are you one of those people who has eight different mascaras in your make-up bag, six of which haven't been used for as long as you can remember?   Do you have a lipstick that you brought around about the same time Christy Brinkley was in fashion?  Was that blush handed down from your mom?  Although this all sounds pretty disgusting, you'll be surprised how many of us keep products way past their life spans, holding on for dear life just in case we may use it once more.