I traveled alone to San Francisco and stayed for 7 days at the Pacific Tradewinds Hostel. The guests and the volunteers welcomed everyone very nice and friendly. Everyday they offered some activities and provided their guests with food all day long :D (peanutbutter jelly sandwiches and ramen). In the evening we often sat together, talked, laughed and played some games. It was always a really warm-hearted atmosphere and I would definitely recommend to stay in this hostel if you plan to visit SF. I had a great trip and made some new friends, too.