This friday night, Karlstad Kommun arranges Kulturnatten (culture night). That means that there will be plenty of activities all ove town during the evening (6 pm to 11 pm), but mostly focused in the Värmland museum and city library area close to Blue Moon Bar. There will be art exhibits, skateboard shows, live music quiz, a film festival, workshops, belly dancing, lots of music and lots of dancing and much more.
The program is only available in Swedish unfortunately but can be found at: http://www.kulturnattenkarlstad.se/program.html
I suggest that you just go there and see what happens some time during the night. Spontaneity is awesome!
Don't miss it :D