Ask HN: Place to hack in Barcelona

Hi fellow HNers, as i will spend a couple of days in Barcelona next week, I was wondering if anyone here who is from that area has a suggestion were i could sit down during the day and get some work done. Desks at Coworking spaces seem to be a bit on the expensive side (30 EUR per day) and i find Cafes to distracting, so maybe there is some cool public place with free wifi ? Doesnt necessarily have to be free but 30 EUR per day is too much ;) TA in advance