I discovered this bar last time I was in Istanbul, and I think my new friends and I went there 2 nights in a row. I figured out what bar it was and went back last night. In warmer weather, the rooftop patio is a lot cooler. They also remodeled the bar and put the bar at the back of the room making it much more spacious. A large Efes is 10TL which is a decent price for what I consider a cool bar. People were pouring in at midnight on a Thursday, and a live gypsy improv band played for free. Great stuff. This is definitely my choice for going out in Istanbul.