Have you ever seen one of these? It's a Dog's Tooth Violet or Erythronium americanum. I purchased them from Dutch Gardens a couple of years ago and they finally have started blooming profusely as of this spring.
I think they're really cool-looking. They also go by the names of Trout Lily, Fawn Lily and Yellow Adder's Tongue Lily. Hmmm, I think I like Dog's Tooth Violet best!
No matter what you call them, they have made a nice addition to my back perennial border. They are hardy down to USDA zone 4 (we're probably in zone 4B so it can get pretty chilly in our garden), they are deer-resistant and will grow in full sun, part sun or in shady conditions. They will grow 10 to 12 inches tall.