Nars Velvet Matte Lip Pencil in Sex Machine - this is a nice shimmery mauve pink. MAC Dervish lip liner is a good match. I like to use a little lip gloss over it to keep it in place (matte lipstick at work = ugh, constant touching up).
NARS Velvet Matte Lip Pencil in 'Cruella' is the best vibrant red lipstick for olive to medium dark skin tones. I got this as a Beauty Insider gift at Sephora, free, and apparently it was made for my skin tone?