it's pretty well hidden in a former industrial area and one has to know that there's this little cafe beside huge chimneys and old abandoned buildings. the surrounding is pretty arty, so there are places where people can spray graffitis, work in studios, etc. the people are very relaxed and friendly and you get good coffee, lemonades as well as homemade cookies and cake. as far as i know they only have open during summer.
by the way 'aaltopelti' means corrugated iron, because the cafe is in a wooden building with a roof out of corrugated iron.