Mertensia maritima; The oyster plant is a plant of beaches and coastal areas. Identification is easy because of its bluish rather succulent leaves. There are no similar plants, certainly not in coastal strips. The expert quickly recognizes the flowers as those of a borage family member (Boraginaceae). Members of the borage family often have seeds containing interesting fatty acids (vegetable oils). I am not aware Mertensia is interesting in that respect. It seems however, it is an edible plant with leaves containing vitamine C.
Myosotis species i.e. Forget-me-nots are members of the Borage family (Boraginaceae). The Icelandic name of this species is Blálilja.