If you're drawing attention to your hands with bling rings or elegant bracelets and watches, your nails need to look their best. I firmly believe the overly fake look sometimes achieved with acrylics is out. Keep your nails short and file them to a nice shape that's more Kate Middleton-class than talkshow-trash.
Push back the cuticles with an orange stick and give them a daily dose of cuticle oil. Keep a hand cream at your desk to replenish your moisture levels - winter heating can really dry skin out.
When it comes to your nail polish colour, dark shades on short nails is a great combo for winter. They need to be short though, to avoid looking like Outrageous Fortune-style talons. Otherwise, nude is chic and great if you are prone to chipping your polish - nicks and scratches are much harder to see on lighter colours.
For something a bit different, try stick-on nail polish. Sally Hansen does a fun range, Salon Effects, with cute designs that will look like you've spent hours doing them.