One of the best shade perennials – pairs well with Hosta – try Allium. Various sizes (these ones are GIANTS). Of the onion family – bulbs. Slow multiplier, but oh so dramatic! Blooms spring/summer then dies back.
Shade garden – Black Mondo Grass. I absolutely LOVE this stuff. Imagine it growing as a border for flowering plants with bright colors. Also makes a great mass planting surrounded by a stone border. Or in planters or flower boxes for contrast.