Craziest thing I did? Took the president's physical fitness test (ca. 1973) including a 1/4 mile run with a fever of 103...didn't realize I had a really bad case of Mono at the time. Immediately went home, and went to the doctor the next day with the worst sore throat I ever had.
(or perhaps the time I ran away from home during Mardi Gras the same year. Was gone a whole week....)