Another early harvesting here in zone 4 country is rhubarb. Mike classifies rhubarb, along with zucchini and anything onion, as "nuisance vegetables." He finds it particularly distressing if my culinary creativity leads me to the use of such vegetables in some baked form like muffins or cake.
Well, rhubarb is hardly a nuisance. Did you know it can be used to clean burned pots and pans, as a hair lightener, as an insecticide, as an ingredient in homemade art paper? Everything you could possibly want to know about rhubarb can be found in The Rhubarb Compendium (http://www.rhubarbinfo.com/). What a thorough resource. I wish I could find a similar site for chives!