As a possible revenue earner, how about drag racing on 23L / 05R, - not much need for it as a runway at present!
Using 23L/05R for car racing was an tongue in cheek idea in 2001 after the Twin Towers attack and subsequent downturn. The runway had only been open a few months.
And in the 70s, the then Airport Director, Gordon Sweetapple, who was a great racing fan, used to test his go kart out on the main runway on a Sunday morning when it was particularly quiet. If ATC required the runway for an aircraft movement, they flashed the edge lights on and off and the go kart then cleared the runway. No safety cases and standard operating procedures in those days.
On a more serious note, many jobs at MAN and other airports are now at risk and I keep my fingers crossed for each and every one of you.