Anemanthele lessoniana - Pheasant's tail grass (syn. Stipa arundinacea) is a plant I would not be without, although I have only paid nodding attention to the present trend for grasses the ability of this grass to light up a winter's day makes it really worth while.
These pictures were taken on a cold but sunny March day a few years ago, I initially grew them in containers because of my damp shady conditions, but through their habit of seeding themselves around, they have proved themselves capable of thriving in the open ground; any errant seedlings are easily removed.
Growing to roughly a meter square they come easily from cold-sown seed like most perennials and the only maintenance they need is to comb out the dead foliage with your gloved hands in spring. I have seen pictures of them used as a repetitive theme at the front of a large herbaceous border and also planted en-mass on a bank side, both are equally effective. A native of New Zealand they are surprisingly hardy here in all but the severest of winters.