Icelandic shares only some and ends up being more like Bulgarian and Portuguese mentioned above - looks like the early Christian influence got the Icelanders too
Monday: mánudagur = moon day
Tuesday: þriðjudagur = 3rd day
Wednesday: miðvikudagur = mid-week day
Thursday: fimmtudagur = 5th day
Friday: föstudagur = fasting day
Saturday: laugardagur = washing day
Sunday: sunnudagur = sun day
Monday = Måndag = Månes dag (Máni's day) - Måne, the brother of Sol. "måne" is also Swedish for "moon"
Tuesday = Tisdag = Tyrs dag (Týr's day, son of Oden)
Wednesday = Onsdag = Odens dag (Oden's day)
Thursday = Torsdag = Tors dag (Thor's day)
Friday = Fredag = Frejas dag (Freyja's day) - some say this day is named after Frigg, and some Norse history seem to indicate that Freyja and Frigg are one and the same goddess that somehow got separated as two in literature
Saturday = Lördag = lögardagen, from old, old Swedish "laugr" (water/waterfall), the day on which you bathe
Sunday = Söndag = Sols dag (Sól's day) - "sol" is Swedish for "sun"