See this bad, slightly blurry pic:
It's NARS Night Flight from the NARS Night Series. It's a lovely shimmery blue, yada, yada, yada... Scrangie and Vampy Varnish have reviews on this series. The reason I posted that picture? It's one coat. This polish is so lovely and deep that one coat is perfect, streak-free and opaque.
I also have Night Porter (the green shimmer). I can't wait to try that one, too. NARS is quickly becoming my favorite polish brand for their formula alone.