I know a woman who was once offered a gig at a bar...the owner asked if she could do about a 40 minute set.
"Sure", she said, "Would you like one song, or more than one?"

She told me that it was only 'slightly' an exaggeration, that the ballad she was thinking of was 'only' about 30 minutes... but she loved the look on his face and knew he wouldn't ask for it.

And many years ago, I knew another woman who had worked up about a 16-17 minute version of "The Lass of Roch Royal" and once tossed it in right after some kid did "Puff the Magic Dragon".... just to make some sort of point.