this is in new york, but actually in the netherlands you very often see people hang their blanket (from the bed) outside their window. i always find that strange... hanging it out like that will make it dirty, no?
as we live in a corner apartment, we have a lot of windows (the reason we decided to take it; so much light!), but all windows have an (insect) screen, so when you open the window, there is still the screen that cannot move. thats pretty common here, but i find it soooo weird! what if you want to throw something out of the window? ;) stick your head out, or just get the crumbs from the tablecloth?