That was and probably still is a staple question on the Newlywed Game. Timeout Chicago decided to ask it in a rather different way. They asked people to confess via sticky notes.
Among the locations listed...
*UIC Men's public bathroom
*A stairwell at the Merchandise Mart
*Adler Planetarium
*On the Metra Train tracks
*On the red line during rush hour
*On a college football field (in the endzone)
And the most shocking...
*During Sunday Mass