The number corresponding to the last minute in a given hour, and the last second in a given minute
The "59-minute rule" is an informal rule in business, whereby (usually near a holiday) employees may be allowed to leave work early, often to beat heavy holiday traffic (the 59 minutes coming from the rule that leaving one full hour early requires the use of leave, whereas leaving 59 minutes early would not)
The number on a button commonly worn by feminist activists in the 1970s; this was based on the claim that a woman earned 59 cents to an equally qualified man's dollar