If you’re going to take the advice to show up at the Box Office, be sure to be nice. Remember that the person behind the window is a human being.
True Story:
jdimbert and I went downtown one night to see a show and were disheartened to see that the only show available at TKTS was “Crap: The Musical!” So, we decided to go to an early dinner and forget about it.
On our way to the restaurant, we passed the theatre that was showing Guys and Dolls, starring Nathan Lane. This was a Tuesday night; he had won the Tony for Best Actor in a Musical the previous Sunday night. Hype for the show was high.
We decided to see if there were any cancellations. It was about 3:45 when we stepped into the Box Office, in line behind two teenage boys. The two of them rudely asked if the woman, “Had any tickets for us, lady?!” She said no, and they left.
When we got our turn, I said, “I guess you don’t, but I might as well ask. Are there any cancellations for tonight’s show?” She told me that there weren’t, yet, but I should check back around 5:00.
We went browsing in Times Square (best place in the world to waste time!) and went back. The boys must have heard the woman tell us to return, because they were there, too, warming themselves by the radiator in the corner of the lobby.
When we approached the window, the woman called out to the two boys, telling them that there were still no cancellations, there would be no cancellations and that they had to leave.
She then smiled at me and sold me two tickets in the center of the second row for $65 apiece. We were close enough to get sweated on. 
So, be nice!