Today I went to the Popsenteret, this is a center for popular music in Oslo. You can go through the history of Norwegian pop music. You will find musical instruments and record collections amongst many other things. In a way, it explains the history of the Norwegian music through the years, and you can use your creativity to play around with music and make your own song and album cover, you can also get your song on MP3.
There are plenty of touch screens for you to play with. So if you are interested in music you will definitely have a great time, even if you're not Norwegian.
NB: The texts and exhibition are in Norwegian but you can get a booklet in English at the reception desk.