They say fiddlehead ferns can kill you if eaten raw, or just give you a nasty G.I. infection. But they're so fun and green and crunchy, I can't resist them. I once picked some on the side of a road in rural Vermont (where I'm told they're the state vegetable), ate them and lived to tell about it.
The ferns above were blanched in boiling, salted water for a few minutes until they were slightly soft then sauteed with chopped onions in some olive oil.