While on a double date with my parents the other night (seeing Avenue Q with your father is just a little weird), my father mentioned that my Zedda (grandfather) used to work in 305 Seventh Avenue.
Zedda was a furrier back in the days when wearing fur wasn't evil. My dad describes him as a very powerful man who could lift a stack of pelts as easily as you might lift a telephone book.
I tried to see what history this building holds but was unable to find much. It is not considered to be architecturally interesting enough for my favorite NYC architecture website and a basic google only gets me some of the businesses in the building. Sorry! It is, however, a piece of family history and I will never walk by it again without thinking about my Zedda.