great topic! I have seen a few shows that blew me away but 2 come to mind.

1) Woman in Mind at ISU Summer Stage 1989. I had never seen such a powerful play.(at that time)

2) My own dear husband(before I met him) As Peter Patrone in the Heidi Cronicles. Beautiful play and his preformance was flawless. I married him after all

I think that the over-use of the standing ovation is an American trait.  Anywhere else in the world ( that I have experience with) it seems that they are rare and well deserved events.  Here everyone seems to leap to their feet ( perhaps their bums are numb) at every play.  I think it should be as described above... a spontaneous "leaping to your feet without hesitation."

I rather like it when the theater is really bad and the audience let's them know it's bad.  I was at a bad play once when an audience member stood up at intermission and announced "I want my money back" and several people agreed with him.  Now that's drama. 

In 1984 I saw a professional dinner theatre production of Annie.  This was closing night and the entire cast of the next show, which happened to be 1776 was in the audience.  This was a theatre in the round.  When the orphans completed "Never Fully Dressed" reprise in Act II, the audience would not stop applauding.  The ovation, and this is not an exaggeration, was over 4 minutes.

To this day I can still see a girl on each corner of the stage and the center entrances to the stage with their arms up, not knowing what to do, and tears streaming down their faces, with huge smiles at the same time.  The best part was that Miss Hannigan did not blow the whistle until the ovation was over.

Truly a memorable night.

John