Who wouldn’t want to go down to the Victoria Theatre early in the morning to see if she could get a ticket for Billy Elliot. Just to wake up and think I can do that is pretty amazing. I stood in line beside a woman from Cologne, Germany who was replacing a ticket that had been stolen from her, but said she had come to London specifically for this weekend to see West End, Live, in Trafalgar Square.
Apparently songs or skits from West End shows appear live on stage in Trafalgar Square on Saturday and Sunday. The performers from the current shows are on stage. People jam the square and stand and watch, just as they would at a rock concert. All of this for free!
I can confirm that the booths are being set up and that the square looks exactly as depicted on the web sites. The second link gives the times that the shows will be playing.
See Festival London or West End Live for more details.