The Open Source show, “Associated,” named after the fire last November that began at the Associated supermarket and devastated the gallery and home of curator/artist Monika Wührer, has been extended this week. The L Magazine’s photo tour gives you a glimpse of this unique, temporary art experience, but you can see the show in the fire-ravaged brownstone during free tours today through Saturday from 1-7pm at 257 17th Street, between 5th and 6th Aves.