The Smile Test
A noted sex therapist realizes that people often lie about
the frequency of their encounters, so he devises a test to
tell for certain how often someone has sex. To prove his
theory, he fills up an auditorium with people, and goes down
the line, asking each person to smile. Using the size of the
person's smile, the therapist is able to guess accurately
until he comes to the last man in line, who is grinning from
ear to ear.
"Twice a day," the therapist guesses, but is surprised when
the man says no. "Once a day, then?" Again the answer is
no. "Twice a week?" "No." "Twice a month?" "No." The man
finally says yes when the doctor gets to "once a year".
The therapist is angry that his theory isn't working, and
asks the man, "What the heck are you so happy about?"
The man answers, "Tonight's the night!"