I just moved to SF about a month ago and the first place I went to to grab something to eat was Golden Boy Pizza...and I live over near Haight.
I discovered Golden Boy about a year ago when I was in the city on vacation just walking around North Beach one night with my girlfriend. We were both starving and pizza sounded good and the price was right. We loved it so much we came back the next day for lunch!
Don't let that fool you however, Golden Boy isn't' the type of place you would want to sit down and enjoy yourself in, you go, eat a few slices, have a beer if you feel like it and you're out the door again. That being said, this is the best pizza I've ever had so its 100% worth it.
The "pies" are large square sheets and could feed a small army, which explains why they are so expensive; they would be perfect for a night in with a few friends watching the game over a few beers. Slices are between $2.50-$3.50.