I had an aircraft approach the opposite end of the runway today as I was taking off. He realised on short finals to the (wrong) runway and turned into the correct circuit. Never said a word...
Last week, as I met him head on in the circuit, I was told over the RT by another visiting aircraft that I was flying the wrong way round the circuit (at my home airfield of nearly 30 years).. For him to then announce a minute later that he was actually in the wrong.
Happens all the time, an occupational hazard in the air it seems.