A friend of mine took a מונית this erev Shabbos while flagging one down in yerushalayim and after arriving at his destination he left the cab while remembering he put his Shabbos hat on the back of the windowsill, he only remembered 30 seconds later which by then the cab was gone , any number or idea he can do or call to possibly find his hat? ( Not that it makes a difference what it was but it was a trionfo, he said he paid around $320).