I read a report that an Emeraude took off with one occupant in Scotland.some years ago. I think it happened in Perth. The flight was of a very short duration due to the fact that the pilot omitted to untie the straps in the empty passenger seat that were holding the control column secured fully back.
More recently, a very disturbing video that I will not link here shows the first flight of a modified turbine aircraft taking off on its cetificating proving flight. The aircraft, when certificated with its original piston engines, incorporated a lock that prevented the throttles from being advanced if the control locks were in place. The modifications incorporated to the new power levers did not incorporate such a lock. The proving flight lasted less than 20 seconds as a result of departing with the control locks in place - and sadly the accident was in no way surviveable.
Last week I am ashamed to admit that I rushed a pre flight and cockpit check due to pax arriving earlier than expected. In my haste I disconnected the yoke lock, but only later, due to a slight discomfort, noticed that the large red rudder lock pole was rubbing against my leg. This was just prior to taxi clearance, and had I not noticed this the hydraulically operated nose wheel steering tiller would have allowed me to taxi without problems. Any subsequent flight though would have been interesting, and the loss of one engine after take off would have been fatal.
Norman Jones, the Tiger Club founder, had placards stating that "ALL AIRCRAFT BITE FOOLS" in all of his club aircraft. I often remind myself that I too am a fool from time to time - so far a lucky one.