I love winter for 3 reasons; boots, coats, and dark lip stick. Of course dark lip colors are not only for winter but I find that harsher colors stay on me better in cooler weather and coats and dark lips compliment each other very well. I have a very dark purple (photographed) by Wet and Wild named Cherry Bomb which I love and is often compared to MAC's "Sin". I layer this color on about 2-3 times so it'll stay and appear darker.
Then I have one other I switch between called Deepest Cherry (more of a burgundy/brown) by Maybelline. I don't wear make up so I usually stick to drug store brands when I do buy cosmetics and I have never had a problem with these two brands. I love dark lips because they really make the rest of the wearers face pop, their eyes are accentuated and their skin is somehow more even and clear all because of a little dark lip. Genius.