Are there any shopping centers, bigger supermarkets, etc... in the Stockholm city center (including Kungsholmen, Ostermalm, etc..) where cars are allowed to park freely (even if only for 1 hour)?
Thank you

Are there any shopping centers, bigger supermarkets, etc... in the Stockholm city center (including Kungsholmen, Ostermalm, etc..) where cars are allowed to park freely (even if only for 1 hour)?
Thank you

No parking in Stockholm is not cheap, if you park out in the close suburbs like Liljeholmen, Solna and such you can find free parking but then you have to take the subway to the center.

Except in the very central parts I think it is free after 5 pm until 9 am or so and on weekends.
Henrik

As #2 states, parking is free in the central residential areas from 5pm-9am. However in the very central shopping areas etc, it's never free.
Parking signs can be a bit tricky to enterpret, but if you see a sign that looks like this: http://www.stockholm.se/TrafikStadsplanering/Parkering/Parkeringstillstand/Boendeparkering/Boendeparkeringsomraden/ , the 5pm-9am rule applies.
Note that the yellow/red sign indicates when the street needs to be cleared for cleaning. (In this case, Thursday 0-6, meaning 12-6am the night between wednesday and thursday.)