As a follow-up to this post, here's another example of how to handle it when no one shows up, from one of the pros.
"When former President Bill Clinton took to the podium on Friday at the Chapman Cultural Center in Spartanburg, he told the audience a story. He said he had just inadvertently walked into the adjacent auditorium and was mortified to see that all the seats were empty. Then, he recounted, he saw a 'tech guy' in the back of the room and said to himself, 'Well, I'll give my best speech to one guy.' He pounded his fist. 'I’ll give my best speech if it's the last thing I do today'."
From The New York Times.