I have never slept in one before. But came awfully close to during a freaky YYZ snowstorm of the century back in 1999. I was scheduled to fly out on CX and was ever so pessimistic that they would cancel the flight because AC and most other U.S. carriers were doing so. The flight status was pending all day and did not get the go until 3 hours prior to scheduled departure time. During the time of the pending status, I was preparing myself to sleep on the bleachers of the terminal so that if they do cancel the flight, I would sleep overnight and still be there if they were to reschedule the flight the following morning as it was virtually impossible to leave the airport vicinity due to traffic woes outside.