An MIT "hack" is an ingenious, benign, and anonymous prank or practical joke, often requiring engineering or scientific expertise and often pulled off under cover of darkness -- instances of campus mischief sometimes coinciding with April Fool's Day, final exams, or commencement. (It should not be confused with the sometimes non-benign phenomenon of computer hacking.) Noteworthy MIT hacks over the years include the legendary Harvard--Yale Football Game Hack (when a weather balloon emblazoned "MIT" popped out of the ground near the 50-yard line), the campus police car found perched on the...