Chickweed was one of the weeds we looked at on a edible weeds walk I went on recently, the guy sent us all e-mails with references to the stuff we learned. Ta da:
Chickweed (Stellaria media)
A delicate winter active green which grows in vegie garden beds and wherever there is rich organic soil. Tastes a bit grassy, but you do get a taste for it. I primarily use it as a salad green, and chopped finely (again because of the long fibres) it makes a decent spinach substitute. Very high in protein and vitamin C and many other good things. More than twice the iron levels of spinach by dry weight. Chickweed is loved by chickens, thus the name.